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Sample records for torso volume change

  1. Quantitative prediction of respiratory tidal volume based on the external torso volume change: a potential volumetric surrogate

    International Nuclear Information System (INIS)

    Li Guang; Arora, Naveen C; Xie Huchen; Ning, Holly; Citrin, Deborah; Kaushal, Aradhana; Zach, Leor; Camphausen, Kevin; Miller, Robert W; Lu Wei; Low, Daniel

    2009-01-01

    An external respiratory surrogate that not only highly correlates with but also quantitatively predicts internal tidal volume should be useful in guiding four-dimensional computed tomography (4DCT), as well as 4D radiation therapy (4DRT). A volumetric surrogate should have advantages over external fiducial point(s) for monitoring respiration-induced motion of the torso, which deforms in synchronization with a patient-specific breathing pattern. This study establishes a linear relationship between the external torso volume change (TVC) and lung air volume change (AVC) by validating a proposed volume conservation hypothesis (TVC = AVC) throughout the respiratory cycle using 4DCT and spirometry. Fourteen patients' torso 4DCT images and corresponding spirometric tidal volumes were acquired to examine this hypothesis. The 4DCT images were acquired using dual surrogates in cine mode and amplitude-based binning in 12 respiratory stages, minimizing residual motion artifacts. Torso and lung volumes were calculated using threshold-based segmentation algorithms and volume changes were calculated relative to the full-exhalation stage. The TVC and AVC, as functions of respiratory stages, were compared, showing a high correlation (r = 0.992 ± 0.005, p 2 = 0.980) without phase shift. The AVC was also compared to the spirometric tidal volumes, showing a similar linearity (slope = 1.030 ± 0.092, R 2 = 0.947). In contrast, the thoracic and abdominal heights measured from 4DCT showed relatively low correlation (0.28 ± 0.44 and 0.82 ± 0.30, respectively) and location-dependent phase shifts. This novel approach establishes the foundation for developing an external volumetric respiratory surrogate.

  2. Quantitative prediction of respiratory tidal volume based on the external torso volume change: a potential volumetric surrogate

    Energy Technology Data Exchange (ETDEWEB)

    Li Guang; Arora, Naveen C; Xie Huchen; Ning, Holly; Citrin, Deborah; Kaushal, Aradhana; Zach, Leor; Camphausen, Kevin; Miller, Robert W [Radiation Oncology Branch, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892 (United States); Lu Wei; Low, Daniel [Department of Radiation Oncology, Washington University School of Medicine, St Louis, MO 63110 (United States)], E-mail: ligeorge@mail.nih.gov

    2009-04-07

    An external respiratory surrogate that not only highly correlates with but also quantitatively predicts internal tidal volume should be useful in guiding four-dimensional computed tomography (4DCT), as well as 4D radiation therapy (4DRT). A volumetric surrogate should have advantages over external fiducial point(s) for monitoring respiration-induced motion of the torso, which deforms in synchronization with a patient-specific breathing pattern. This study establishes a linear relationship between the external torso volume change (TVC) and lung air volume change (AVC) by validating a proposed volume conservation hypothesis (TVC = AVC) throughout the respiratory cycle using 4DCT and spirometry. Fourteen patients' torso 4DCT images and corresponding spirometric tidal volumes were acquired to examine this hypothesis. The 4DCT images were acquired using dual surrogates in cine mode and amplitude-based binning in 12 respiratory stages, minimizing residual motion artifacts. Torso and lung volumes were calculated using threshold-based segmentation algorithms and volume changes were calculated relative to the full-exhalation stage. The TVC and AVC, as functions of respiratory stages, were compared, showing a high correlation (r = 0.992 {+-} 0.005, p < 0.0001) as well as a linear relationship (slope = 1.027 {+-} 0.061, R{sup 2} = 0.980) without phase shift. The AVC was also compared to the spirometric tidal volumes, showing a similar linearity (slope = 1.030 {+-} 0.092, R{sup 2} = 0.947). In contrast, the thoracic and abdominal heights measured from 4DCT showed relatively low correlation (0.28 {+-} 0.44 and 0.82 {+-} 0.30, respectively) and location-dependent phase shifts. This novel approach establishes the foundation for developing an external volumetric respiratory surrogate.

  3. Changes in the volume and circumference of the torso, leg and arm after cycling in the heat determined using 3D whole body scanners : conference paper, Lugano, Switzerland,

    NARCIS (Netherlands)

    Hein, Daanen; Vonk, L.A.

    2016-01-01

    Whole body volume changes due to sweat loss after exercise in the heat are well documented, but little is known about the relative contribution of the torso and extremities to these volume changes. It is the purpose of this study to quantify these effects. Therefore, seven healthy male subjects were

  4. Emergency department spirometric volume and base deficit delineate risk for torso injury in stable patients

    Directory of Open Access Journals (Sweden)

    Sipe Eilynn K

    2004-01-01

    Full Text Available Abstract Background We sought to determine torso injury rates and sensitivities associated with fluid-positive abdominal ultrasound, metabolic acidosis (increased base deficit and lactate, and impaired pulmonary physiology (decreased spirometric volume and PaO2/FiO2. Methods Level I trauma center prospective pilot and post-pilot study (2000–2001 of stable patients. Increased base deficit was 2.5 mmol/L in ethanol-negative and ≥ 3.0 mmol/L in ethanol-positive patients. Decreased PaO2/FiO2 was Results Of 215 patients, 66 (30.7% had a torso injury (abdominal/pelvic injury n = 35 and/or thoracic injury n = 43. Glasgow Coma Scale score was 14.8 ± 0.5 (13–15. Torso injury rates and sensitivities were: abdominal ultrasound negative and normal base deficit, lactate, PaO2/FiO2, and spirometric volume – 0.0% & 0.0%; normal base deficit and normal spirometric volume – 4.2% & 4.5%; chest/abdominal soft tissue injury – 37.8% & 47.0%; increased lactate – 39.7% & 47.0%; increased base deficit – 41.3% & 75.8%; increased base deficit and/or decreased spirometric volume – 43.8% & 95.5%; decreased PaO2/FiO2 – 48.9% & 33.3%; positive abdominal ultrasound – 62.5% & 7.6%; decreased spirometric volume – 73.4% & 71.2%; increased base deficit and decreased spirometric volume – 82.9% & 51.5%. Conclusions Trauma patients with normal base deficit and spirometric volume are unlikely to have a torso injury. Patients with increased base deficit or lactate, decreased spirometric volume, decreased PaO2/FiO2, or positive FAST have substantial risk for torso injury. Increased base deficit and/or decreased spirometric volume are highly sensitive for torso injury. Base deficit and spirometric volume values are readily available and increase or decrease the suspicion for torso injury.

  5. Predicting significant torso trauma.

    Science.gov (United States)

    Nirula, Ram; Talmor, Daniel; Brasel, Karen

    2005-07-01

    Identification of motor vehicle crash (MVC) characteristics associated with thoracoabdominal injury would advance the development of automatic crash notification systems (ACNS) by improving triage and response times. Our objective was to determine the relationships between MVC characteristics and thoracoabdominal trauma to develop a torso injury probability model. Drivers involved in crashes from 1993 to 2001 within the National Automotive Sampling System were reviewed. Relationships between torso injury and MVC characteristics were assessed using multivariate logistic regression. Receiver operating characteristic curves were used to compare the model to current ACNS models. There were a total of 56,466 drivers. Age, ejection, braking, avoidance, velocity, restraints, passenger-side impact, rollover, and vehicle weight and type were associated with injury (p < 0.05). The area under the receiver operating characteristic curve (83.9) was significantly greater than current ACNS models. We have developed a thoracoabdominal injury probability model that may improve patient triage when used with ACNS.

  6. Spacesuit Soft Upper Torso Sizing Systems

    Science.gov (United States)

    Graziosi, David; Splawn, Keith

    2011-01-01

    The passive sizing system consists of a series of low-profile pulleys attached to the front and back of the shoulder bearings on a spacesuit soft upper torso (SUT), textile cord or stainless steel cable, and a modified commercial ratchet mechanism. The cord/cable is routed through the pulleys and attached to the ratchet mechanism mounted on the front of the spacesuit within reach of the suited subject. Upon actuating the ratchet mechanism, the shoulder bearing breadth is changed, providing variable upper torso sizing. The active system consists of a series of pressurizable nastic cells embedded into the fabric layers of a spacesuit SUT. These cells are integrated to the front and back of the SUT and are connected to an air source with a variable regulator. When inflated, the nastic cells provide a change in the overall shoulder bearing breadth of the spacesuit and thus, torso sizing. The research focused on the development of a high-performance sizing and actuation system. This technology has application as a suit-sizing mechanism to allow easier suit entry and more accurate suit fit with fewer torso sizes than the existing EMU (Extravehicular Mobility Unit) suit system. This advanced SUT will support NASA s Advanced EMU Evolutionary Concept of a two-sizes-fit-all upper torso for replacement of the current EMU hard upper torso (HUT). Both the passive and nastic sizing system approaches provide astronauts with real-time upper torso sizing, which translates into a more comfortable suit, providing enhanced fit resulting in improved crewmember performance during extravehicular activity. These systems will also benefit NASA by reducing flight logistics as well as overall suit system cost. The nastic sizing system approach provides additional structural redundancy over existing SUT designs by embedding additional coated fabric and uncoated fabric layers. Two sizing systems were selected to build into a prototype SUT: one active and one passive. From manned testing, it

  7. Segmental torso masses in adolescent idiopathic scoliosis.

    Science.gov (United States)

    Keenan, Bethany E; Izatt, Maree T; Askin, Geoffrey N; Labrom, Robert D; Pettet, Graeme J; Pearcy, Mark J; Adam, Clayton J

    2014-08-01

    Adolescent idiopathic scoliosis is the most common type of spinal deformity whose aetiology remains unclear. Studies suggest that gravitational forces in the standing position play an important role in scoliosis progression, therefore anthropometric data is required to develop biomechanical models of the deformity. Few studies have analysed the trunk by vertebral level and none have performed investigations of the scoliotic trunk. The aim of this study was to determine the centroid, thickness, volume and estimated mass, for sections of the scoliotic trunk. Existing low-dose CT scans were used to estimate vertebral level-by-level torso masses for 20 female adolescent idiopathic scoliosis patients. ImageJ processing software was used to analyse the CT images and enable estimation of the segmental torso mass corresponding to each vertebral level. The patients' mean age was 15.0 (SD 2.7) years with mean major Cobb angle of 52 (SD 5.9)° and mean patient weight of 58.2 (SD 11.6) kg. The magnitude of torso segment mass corresponding to each vertebral level increased by 150% from 0.6kg at T1 to 1.5kg at L5. Similarly, segmental thickness from T1-L5 increased inferiorly from a mean 18.5 (SD 2.2) mm at T1 to 32.8 (SD 3.4) mm at L5. The mean total trunk mass, as a percentage of total body mass, was 27.8 (SD 0.5) % which was close to values reported in previous literature. This study provides new anthropometric reference data on segmental (vertebral level-by-level) torso mass in adolescent idiopathic scoliosis patients, useful for biomechanical models of scoliosis progression and treatment. Copyright © 2014 Elsevier Ltd. All rights reserved.

  8. Radiology trainer. Torso, internal organs and vessels. 2. ed.

    International Nuclear Information System (INIS)

    Staebler, Axel; Erlt-Wagner, Birgit

    2013-01-01

    The radiology training textbook is based on case studies of the clinical experience, including radiological imaging and differential diagnostic discussion. The scope of this volume covers the torso, internal organs and vessels. The following issues are discussed: lungs, pleura, mediastinum; heart and vascular system; upper abdomen organs; gastrointestinal tract; urogenital system.

  9. An improved Virtual Torso phantom

    International Nuclear Information System (INIS)

    Kramer, Gary H; Crowley, Paul

    2000-01-01

    The virtual phantom that was previously designed by the Human Monitoring Laboratory had some limitations. It contained no sternum and the ribs extended all the way round the torso, whereas in reality the central part of the chest is covered with a mixture of cartilage (ribs) and bone (sternum). The ribs were located below the chest wall which added to the thickness of the chest wall. The lungs did not touch the inner surface of the chest wall along their length due to the differences in curvature between the ellipsoidal lungs and the ellipsoidal cylinder that defined the torso. As a result there was extra intervening tissue between the lungs and the chest wall. This was shown to have a noticeable effect on the simulation of low energy photons. The virtual phantom has been redesigned and comparison of measured and calculated counting efficiencies shows that it is a good representation of both of LLNL or JAERI at all photon energies measured. The redesigned virtual phantom agrees to within 11% of the torsos' counting efficiency over the energy range 17 - 240 keV. Before modification, the virtual phantom's counting efficiency was a of factor three lower at 17 keV and a factor of two lower at 20 keV; now it is within 5% at 17 keV and within 10% at 20 keV. This phantom can now be reliably used to simulate lung counting. The virtual phantom still contains no sternum and the ribs extend all the way round the torso, whereas in reality the central part of the chest is covered with cartilage (ribs) and bone (sternum). However, the above results indicate that this is not a major flaw in the design of the virtual phantom, as agreement between the Monte Carlo results and experimental data is good. (author)

  10. Plasma volume changes during hypoglycaemia

    DEFF Research Database (Denmark)

    Hilsted, J; Bendtsen, F; Christensen, N J

    1990-01-01

    To investigate whether previously reported changes in venous blood volume and composition induced by acute hypoglycaemia in humans are representative for the entire body we measured erythrocyte 51Cr content, haematocrit, plasma volume, intravascular albumin content and transcapillary escape rate...... of albumin in arterial and venous blood in seven healthy subjects before and during insulin-induced hypoglycaemia. In both vascular sites blood 51Cr content and the haematocrit increased, plasma volume and intravascular albumin content decreased and the transcapillary escape rate of albumin increased during...

  11. Plasma volume changes during hypoglycaemia

    DEFF Research Database (Denmark)

    Hilsted, J; Frandsen, Henrik Lund; Christensen, N J

    1991-01-01

    -induced hypoglycaemia with total autonomic blockade (alpha-adrenoceptor blockade combined with beta-adrenoceptor blockade and atropine); and insulin-induced hypoglycaemia without any autonomic blockade. In the experiments without autonomic blockade the peripheral venous hematocrit increased, plasma volume decreased......, intravascular albumin content decreased and the transcapillary escape rate of albumin increased. In both experiments with autonomic blockade the increase in venous haematocrit was abolished, yet plasma volume decreased, intravascular albumin content decreased and the transcapillary escape rate of albumin...... increased in these experiments. Thus, the changes in plasma volume and composition in response to hypoglycaemia are due to the combined actions of adrenaline and of insulin....

  12. Multimodal image registration of the scoliotic torso for surgical planning

    International Nuclear Information System (INIS)

    Harmouche, Rola; Cheriet, Farida; Labelle, Hubert; Dansereau, Jean

    2013-01-01

    This paper presents a method that registers MRIs acquired in prone position, with surface topography (TP) and X-ray reconstructions acquired in standing position, in order to obtain a 3D representation of a human torso incorporating the external surface, bone structures, and soft tissues. TP and X-ray data are registered using landmarks. Bone structures are used to register each MRI slice using an articulated model, and the soft tissue is confined to the volume delimited by the trunk and bone surfaces using a constrained thin-plate spline. The method is tested on 3 pre-surgical patients with scoliosis and shows a significant improvement, qualitatively and using the Dice similarity coefficient, in fitting the MRI into the standing patient model when compared to rigid and articulated model registration. The determinant of the Jacobian of the registration deformation shows higher variations in the deformation in areas closer to the surface of the torso. The novel, resulting 3D full torso model can provide a more complete representation of patient geometry to be incorporated in surgical simulators under development that aim at predicting the effect of scoliosis surgery on the external appearance of the patient’s torso

  13. Multimodal image registration of the scoliotic torso for surgical planning

    Science.gov (United States)

    2013-01-01

    Background This paper presents a method that registers MRIs acquired in prone position, with surface topography (TP) and X-ray reconstructions acquired in standing position, in order to obtain a 3D representation of a human torso incorporating the external surface, bone structures, and soft tissues. Methods TP and X-ray data are registered using landmarks. Bone structures are used to register each MRI slice using an articulated model, and the soft tissue is confined to the volume delimited by the trunk and bone surfaces using a constrained thin-plate spline. Results The method is tested on 3 pre-surgical patients with scoliosis and shows a significant improvement, qualitatively and using the Dice similarity coefficient, in fitting the MRI into the standing patient model when compared to rigid and articulated model registration. The determinant of the Jacobian of the registration deformation shows higher variations in the deformation in areas closer to the surface of the torso. Conclusions The novel, resulting 3D full torso model can provide a more complete representation of patient geometry to be incorporated in surgical simulators under development that aim at predicting the effect of scoliosis surgery on the external appearance of the patient’s torso. PMID:23289431

  14. Colloid volume loading does not mitigate decreases in central blood volume during simulated hemorrhage while heat stressed

    DEFF Research Database (Denmark)

    Crandall, Craig G; Wilson, Thad E; Marving, Jens

    2012-01-01

    attenuates the reduction in regional blood volumes during a simulated hemorrhagic challenge imposed via lower-body negative pressure (LBNP). Seven subjects underwent 30 mmHg LBNP while normothermic, during passive heat stress (increased internal temperature ~1°C), and while continuing to be heated after...... intravenous colloid volume loading (11 ml/kg). Relative changes in torso and regional blood volumes were determined by gamma camera imaging with technetium-99m labeled erythrocytes. Heat stress reduced blood volume in all regions (ranging from 7 to 16%), while subsequent volume loading returned those values...... to normothermic levels. While normothermic, LBNP reduced blood volume in all regions (torso: 22±8%; heart: 18±6%; spleen: 15±8%). During LBNP while heat stressed, the reductions in blood volume in each region were markedly greater when compared to LBNP while normothermic (torso: 73±2%; heart: 72±3%; spleen: 72...

  15. Volume changes in unrestrained structural lightweight concrete.

    Science.gov (United States)

    1964-08-01

    In this study a comparator-type measuring system was developed to accurately determine volume change characteristics of one structural lightweight concrete. The specific properties studied were the coefficient of linear thermal expansion and unrestra...

  16. Saturation volume changes and resistivity changes in nickel

    International Nuclear Information System (INIS)

    Birtcher, R.C.; Blewitt, T.H.

    1976-01-01

    Saturation defect concentrations generated by thermal neutron irradiation of 235 U doped nickel at liquid helium temperature were measured by changes in electrical resistivity and volume. The experimental procedure is described

  17. High resolution gas volume change sensor

    International Nuclear Information System (INIS)

    Dirckx, Joris J. J.; Aernouts, Jef E. F.; Aerts, Johan R. M.

    2007-01-01

    Changes of gas quantity in a system can be measured either by measuring pressure changes or by measuring volume changes. As sensitive pressure sensors are readily available, pressure change is the commonly used technique. In many physiologic systems, however, buildup of pressure influences the gas exchange mechanisms, thus changing the gas quantity change rate. If one wants to study the gas flow in or out of a biological gas pocket, measurements need to be done at constant pressure. In this article we present a highly sensitive sensor for quantitative measurements of gas volume change at constant pressure. The sensor is based on optical detection of the movement of a droplet of fluid enclosed in a capillary. The device is easy to use and delivers gas volume data at a rate of more than 15 measurements/s and a resolution better than 0.06 μl. At the onset of a gas quantity change the sensor shows a small pressure artifact of less than 15 Pa, and at constant change rates the pressure artifact is smaller than 10 Pa or 0.01% of ambient pressure

  18. Dissociating contributions of head and torso to spatial reference frames

    DEFF Research Database (Denmark)

    Alsmith, Adrian J T; Ferrè, Elisa R; Longo, Matthew R.

    2017-01-01

    contribution of each part to spatial judgments. Both the head and the torso contributed to judgements, though with greater contributions from the torso. A second experiment manipulating visual contrast of the torso showed that this does not reflect low-level differences in visual salience between body parts....... Our results demonstrate that spatial perspective-taking relies on a weighted combination of reference frames centred on different parts of the body....

  19. LARM PKM solutions for torso design in humanoid robots

    Science.gov (United States)

    Ceccarelli, Marco

    2014-12-01

    Human-like torso features are essential in humanoid robots. In this paper problems for design and operation of solutions for a robotic torso are discussed by referring to experiences and designs that have been developed at Laboratory of Robotics and Mechatronics (LARM) in Cassino, Italy. A new solution is presented with conceptual views as waist-trunk structure that makes a proper partition of the performance for walking and arm operations as sustained by a torso.

  20. Validation of stereophotogrammetry of the human torso.

    Science.gov (United States)

    Lee, Juhun; Kawale, Manas; Merchant, Fatima A; Weston, June; Fingeret, Michelle C; Ladewig, Dianne; Reece, Gregory P; Crosby, Melissa A; Beahm, Elisabeth K; Markey, Mia K

    2011-02-15

    The objective of this study was to determine if measurements of breast morphology computed from three-dimensional (3D) stereophotogrammetry are equivalent to traditional anthropometric measurements obtained directly on a subject using a tape measure. 3D torso images of 23 women ranged in age from 36 to 63 who underwent or were scheduled for breast reconstruction surgery were obtained using a 3dMD torso system (3Q Technologies Inc., Atlanta, GA). Two different types (contoured and line-of-sight distances) of a total of nine distances were computed from 3D images of each participant. Each participant was photographed twice, first without fiducial points marked (referred to as unmarked image) and second with fiducial points marked prior to imaging (referred to as marked image). Stereophotogrammetry was compared to traditional direct anthropometry, in which measurements were taken with a tape measure on participants. Three statistical analyses were used to evaluate the agreement between stereophotogrammetry and direct anthropometry. Seven out of nine distances showed excellent agreement between stereophotogrammetry and direct anthropometry (both marked and unmarked images). In addition, stereophotogrammetry from the unmarked image was equivalent to that of the marked image (both line-of-sight and contoured distances). A lower level of agreement was observed for some measures because of difficulty in localizing more vaguely defined fiducial points, such as lowest visible point of breast mound, and inability of the imaging system in capturing areas obscured by the breast, such as the inframammary fold. Stereophotogrammetry from 3D images obtained from the 3dMD torso system is effective for quantifying breast morphology. Tools for surgical planning and evaluation based on stereophotogrammetry have the potential to improve breast surgery outcomes.

  1. Dosimetry in a torso phantom during a mammography

    International Nuclear Information System (INIS)

    Hernandez O, M.; Duran M, H. A.; Pinedo S, A.; Salas L, M. A.; Hernandez D, V. M.; Vega C, H. R.; Rivera M, T.; Ventura M, J.

    2009-10-01

    Two dosimetric magnitudes, the absorbed dose and the kerma in air to the entrance of torso have been determined. These dosimetric magnitudes are due to the radiation that is dispersed in the mammary gland when the patient undergoes a mammography study. The kerma to the entrance of the torso and the absorbed dose by the torso was obtained in a phantom of paraffin and with thermoluminescent dosemeters of ZrO 2 . The dosemeters were placed on the surface of the torso phantom while the mammography was carried out. (author)

  2. 49 CFR 572.165 - Upper and lower torso assemblies and torso flexion test procedure.

    Science.gov (United States)

    2010-10-01

    ...) ANTHROPOMORPHIC TEST DEVICES Hybrid III Six-Year-Old Weighted Child Test Dummy § 572.165 Upper and lower torso... determine the stiffness effects of the lumbar spine (specified in 49 CFR 572.125(a)), including cable... bushing (specified in 49 CFR 572.125(a)), nut (specified in 49 CFR 572.125(a)), spine box weighting plates...

  3. 49 CFR 572.145 - Upper and lower torso assemblies and torso flexion test procedure.

    Science.gov (United States)

    2010-10-01

    ...) ANTHROPOMORPHIC TEST DEVICES 3-year-Old Child Crash Test Dummy, Alpha Version § 572.145 Upper and lower torso... lumbar spine and abdomen of a fully assembled dummy (drawing 210-0000) to flexion articulation between... in paragraph (c) of this section, the lumbar spine-abdomen assembly shall flex by an amount that...

  4. 49 CFR 572.125 - Upper and lower torso assemblies and torso flexion test procedure.

    Science.gov (United States)

    2010-10-01

    ... of the dummy, the pull cable, and the load cell as shown in Figure N5. (7) Apply a tension force in the midsagittal plane to the pull cable as shown in Figure N5 at any upper torso deflection rate... determine the stiffness effects of the lumbar spine (drawing 127-3002), including cable (drawing 127-8095...

  5. Understanding 3D human torso shape via manifold clustering

    Science.gov (United States)

    Li, Sheng; Li, Peng; Fu, Yun

    2013-05-01

    Discovering the variations in human torso shape plays a key role in many design-oriented applications, such as suit designing. With recent advances in 3D surface imaging technologies, people can obtain 3D human torso data that provide more information than traditional measurements. However, how to find different human shapes from 3D torso data is still an open problem. In this paper, we propose to use spectral clustering approach on torso manifold to address this problem. We first represent high-dimensional torso data in a low-dimensional space using manifold learning algorithm. Then the spectral clustering method is performed to get several disjoint clusters. Experimental results show that the clusters discovered by our approach can describe the discrepancies in both genders and human shapes, and our approach achieves better performance than the compared clustering method.

  6. Radiology trainer. Torso, internal organs and vessels. 2. ed.; Radiologie-Trainer. Koerperstamm, innere Organe und Gefaesse

    Energy Technology Data Exchange (ETDEWEB)

    Staebler, Axel [Orthopaedische Klinik Harlaching, Muenchen (Germany). Radiologische Praxis; Erlt-Wagner, Birgit (eds.) [Klinikum der Universitaet Muenchen (Germany). Inst. fuer Klinische Radiologie

    2013-11-01

    The radiology training textbook is based on case studies of the clinical experience, including radiological imaging and differential diagnostic discussion. The scope of this volume covers the torso, internal organs and vessels. The following issues are discussed: lungs, pleura, mediastinum; heart and vascular system; upper abdomen organs; gastrointestinal tract; urogenital system.

  7. Relative blood volume changes underestimate total blood volume changes during hemodialysis

    NARCIS (Netherlands)

    Dasselaar, Judith J.; Lub-de Hooge, Marjolijn N.; Pruim, Jan; Nijnuis, Hugo; Wiersum, Anneke; de Jong, Paul E.; Huisman, Roel M.; Franssen, Casper F. M.

    Background: Measurements of relative blood volume changes (ARBV) during hemodialysis (HD) are based on hemoconcentration and assume uniform mixing of erythrocytes and plasma throughout the circulation. However, whole-body hematocrit (Ht) is lower than systemic Ht. During HD, a change in the ratio

  8. The effect of patient migration in bed on torso elevation.

    Science.gov (United States)

    Wiggermann, Neal; Kotowski, Susan; Davis, Kermit; VanGilder, Catherine

    2015-01-01

    Elevating the hospital head of bed (HOB) to at least 30° is recommended practice to reduce the risk of ventilator-associated pneumonia (VAP) in mechanically ventilated patients. However, this common practice prescribes the position of the bed and not of the patient, which could be significantly different. The aim of this research was to determine the relationship between patient migration in bed and anatomic torso angle. Ten healthy participants were positioned in a hospital bed that was raised from flat to 30° and 45° HOB elevations. Prior to bed movement, participants were aligned to different locations along the length of the bed to represent different amounts of migration. A motion capture system was used to measure torso angle and migration toward the foot of the bed. The relationship between torso angle and migration was estimated by linear regression. Patient migration resulted in lower torso angles for both 30° and 45° HOB articulations. A migration of 10 cm resulted in a loss of 9.1° and 13.0° of torso angle for HOB articulations of 30° and 45°, respectively (for 30° articulations: (Equation is included in full-text article.)= -0.91, R = .96; for 45° articulations: (Equation is included in full-text article.)= -1.30, R = .98). Migration toward the foot of the bed flattens the torso. To maintain a torso angle that is likely to protect against VAP, healthcare providers need to manage both HOB angle and migration. Protocols and equipment that minimize patient migration will help support effective clinical practice. Future research on patient migration, as it relates to VAP or other outcomes, should measure patient torso angle to allow accurate translation of the results to care practice.

  9. Calibration of lung counter using a CT model of Torso phantom and Monte Carlo method

    International Nuclear Information System (INIS)

    Zhang Binquan; Ma Jizeng; Yang Duanjie; Liu Liye; Cheng Jianping

    2006-01-01

    Tomography image of a Torso phantom was obtained from CT-Scan. The Torso phantom represents the trunk of an adult man that is 170 cm high and weight of 65 kg. After these images were segmented, cropped, and resized, a 3-dimension voxel phantom was created. The voxel phantom includes more than 2 million voxels, which size was 2.73 mm x 2.73 mm x 3 mm. This model could be used for the calibration of lung counter with Monte Carlo method. On the assumption that radioactive material was homogeneously distributed throughout the lung, counting efficiencies of a HPGe detector in different positions were calculated as Adipose Mass fraction (AMF) was different in the soft tissue in chest. The results showed that counting efficiencies of the lung counter changed up to 67% for 17.5 keV γ ray and 20% for 25 keV γ ray when AMF changed from 0 to 40%. (authors)

  10. Morphometric analysis of torso arterial anatomy with implications for resuscitative aortic occlusion.

    Science.gov (United States)

    Stannard, Adam; Morrison, Jonathan J; Sharon, Danny J; Eliason, Jonathan L; Rasmussen, Todd E

    2013-08-01

    Hemorrhage is a leading cause of death in military and civilian trauma. Despite the importance of the aorta as a site of hemorrhage control and resuscitative occlusion, detailed knowledge of its morphometry is lacking. The objective of this study was to characterize aortic morphometry in a trauma population, including quantification of distances as well as and diameters and definition of relevant aortic zones. Center line measures were made (Volume Viewer) from contrast computed tomography (CT) scans of male trauma patients (18-45 years). Aortic zones were defined based on branch arteries. Zone I includes left subclavian to celiac; Zone II includes celiac to caudal renal; Zone III includes caudal renal to aortic bifurcation. Zone lengths were calculated and correlated to a novel external measure of torso extent (symphysis pubis to sternal notch). Eighty-eight males (mean [SD], 28 [4] years) had CT scans for the study. The median (interquartile range) lengths (mm) of Zones I, II, and III were 210 mm (202-223 mm), 33 mm (28-38 mm), and 97 mm (91-103 mm), respectively. Median aortic diameters at the left subclavian, celiac, and lowest renal arteries were 21 mm (20-23 mm), 18 mm (16-19 mm), and 15 mm (14-16 mm), respectively, and the terminal aortic diameter was 14 mm (13-15 mm). The correlation of determination for descending aortic length (all zones) against torso extend was r = 0.454. This study provides a morphometric analysis of the aorta in a male population, demonstrating consistency of length and diameter while defining distinct axial zones. Findings suggest that center line aortic distances correlate with a simple, external measure of torso extent. Morphometric study of the aorta using CT data may facilitate the development and implementation of occlusion techniques to manage noncompressible torso, pelvic, and junctional femoral hemorrhage.

  11. Clinically significant change in stroke volume in pulmonary hypertension

    NARCIS (Netherlands)

    van Wolferen, S.A.; van de Veerdonk, M.C.; Mauritz, G.J.; Jacobs, W.; Marcus, J.T.; Marques, K.M.J.; Bronzwaer, J.G.F.; Heijmans, M.W.; Boonstra, A.; Postmus, P.E.; Westerhof, N.; Noordegraaf, A.V.

    2011-01-01

    Background: Stroke volume is probably the best hemodynamic parameter because it reflects therapeutic changes and contains prognostic information in pulmonary hypertension (PH). Stroke volume directly reflects right ventricular function in response to its load, without the correction of compensatory

  12. Contrast media osmolality and plasma volume changes

    International Nuclear Information System (INIS)

    Hine, A.L.; Lui, D.; Dawson, P.; Middlesex Hospital, London

    1985-01-01

    A theoretical and experimental study of the plasma volume expansion consequent on the hyperosmolality of contrast media is presented. In the case of the ratio 1.5 media theory and experiment coincide closely but in the case of the ratio 3 media the observed changes exceed the predicted. It is proposed that this is due partly to the slower diffusion of the ratio 3 media out of the intravascular space and partly due to the fact that the osmotic load presented by these media is greater than would be expected from a study of their commercial solutions in which osmolality is reduced by molecular aggregation. The implications for the relative haemodynamic effects of different contrast media are discussed. The osmotic effects of contrast media also play a part in determining the image quality achievable in intravenous digital subtraction angiography (IV-DSA). It is predicted that ratio 3 contrast media will give better quality images in IV-DSA than ratio 1.5 media. (orig.)

  13. Estimating the rates of mass change, ice volume change and snow volume change in Greenland from ICESat and GRACE data

    NARCIS (Netherlands)

    Slobbe, D.C.; Ditmar, P.G.; Lindenbergh, R.C.

    2008-01-01

    The focus of this paper is on the quantification of ongoing mass and volume changes over the Greenland ice sheet. For that purpose, we used elevation changes derived from the Ice, Cloud, and land Elevation Satellite (ICESat) laser altimetry mission and monthly variations of the Earth’s gravity field

  14. Human choice and climate change. Volume 1: The societal framework

    International Nuclear Information System (INIS)

    Raynor, S.; Malone, E.

    1998-01-01

    This book is Volume 1 of a four-volume set which assesses social science research that is relevant to global climate change from a wide-ranging interdisciplinary perspective. Attention is focused on the societal framework as it relates to climate change. This series is indispensable reading for scientists and engineers wishing to make an effective contribution to the climate change policy debate

  15. Torso and Bowing Arm Three-Dimensional Joint Kinematics of Elite Cellists: Clinical and Pedagogical Implications for Practice.

    Science.gov (United States)

    Hopper, Luke; Chan, Cliffton; Wijsman, Suzanne; Ackland, Timothy; Visentin, Peter; Alderson, Jacqueline

    2017-06-01

    Elite cello playing requires complex and refined motor control. Cellists are prone to right shoulder and thoracolumbar injuries. Research informing injury management of cellists and cello pedagogy is limited. The aims of this study were to quantify the torso, right shoulder, and elbow joint movement used by elite cellists while performing a fundamental playing task, a C major scale, under two volume conditions. An eight degrees of freedom upper limb biomechanical model was applied to 3D motion capture data of the torso, upper arm, and forearm for 31 cellists with a mean experience of 19.4 yrs (SD 9.1). Two-factor ANOVA compared the joint positions between the four cello strings and two volume conditions. Significant (ppedagogical practices.

  16. The effects of scoliosis and subsequent surgery on the shape of the torso

    Directory of Open Access Journals (Sweden)

    Adrian Gardner

    2017-11-01

    Full Text Available Abstract Background Adolescent idiopathic scoliosis (AIS causes asymmetry of the torso, and this is often the primary concern of patients. Surgery aims to minimise the visual asymmetry. It is not clear how scoliosis makes the torso asymmetric or how scoliosis surgery changes that asymmetry when compared to the distribution of asymmetries seen in a non-scoliotic group of normal controls. Methods Surface topography images were captured for a group with AIS both pre-operatively and post-operatively. Identifiable points were compared between the images to identify the effects of AIS on the shape of the torso by looking at the relative heights and distances from the midline of the shoulders, axillae and waist in a two-dimensional coronal view. This was then compared to a previously reported group of normal non-scoliotic children to analyse whether surgery recreated normality. Results There were 172 pairs of images with 164 females and 8 males, mean age at pre-operative scan of 13.7 years. The normal group was 642 images (237 females and 405 males from 116 males and 79 females, mean age of 12.5 years. The curve patterns seen in the scoliotic group matched the patterns of a main thoracic curve (n = 146 and main thoracolumbar curve (n = 26. The asymmetries seen in both shoulders, axillae and waist were different between the two different types of curve. Across both groups, the shoulder asymmetry was less than that of the corresponding axillae. There was a statistically significant reduction in all asymmetries following surgery in the main thoracic group (p < 0.001. This was not seen in the main thoracolumbar group, thought to be due to the small sample size. In the main thoracic group, there were statistically significant differences in the asymmetries between the post-operative and normal groups in the shoulders and axillae (p < 0.001 but not the waist. Conclusions This paper demonstrates quantitatively the range of asymmetries seen

  17. Clinically significant change in stroke volume in pulmonary hypertension.

    Science.gov (United States)

    van Wolferen, Serge A; van de Veerdonk, Marielle C; Mauritz, Gert-Jan; Jacobs, Wouter; Marcus, J Tim; Marques, Koen M J; Bronzwaer, Jean G F; Heymans, Martijn W; Boonstra, Anco; Postmus, Pieter E; Westerhof, Nico; Vonk Noordegraaf, Anton

    2011-05-01

    Stroke volume is probably the best hemodynamic parameter because it reflects therapeutic changes and contains prognostic information in pulmonary hypertension (PH). Stroke volume directly reflects right ventricular function in response to its load, without the correction of compensatory increased heart rate as is the case for cardiac output. For this reason, stroke volume, which can be measured noninvasively, is an important hemodynamic parameter to monitor during treatment. However, the extent of change in stroke volume that constitutes a clinically significant change is unknown. The aim of this study was to determine the minimal important difference (MID) in stroke volume in PH. One hundred eleven patients were evaluated at baseline and after 1 year of follow-up with a 6-min walk test (6MWT) and cardiac MRI. Using the anchor-based method with 6MWT as the anchor, and the distribution-based method, the MID of stroke volume change could be determined. After 1 year of treatment, there was, on average, a significant increase in stroke volume and 6MWT. The change in stroke volume was related to the change in 6MWT. Using the anchor-based method, an MID of 10 mL in stroke volume was calculated. The distribution-based method resulted in an MID of 8 to 12 mL. Both methods showed that a 10-mL change in stroke volume during follow-up should be considered as clinically relevant. This value can be used to interpret changes in stroke volume during clinical follow-up in PH.

  18. KCNQ1 channels sense small changes in cell volume

    DEFF Research Database (Denmark)

    Grunnet, Morten; Jespersen, Thomas; MacAulay, Nanna

    2003-01-01

    Many important physiological processes involve changes in cell volume, e.g. the transport of salt and water in epithelial cells and the contraction of cardiomyocytes. In this study, we show that voltage-gated KCNQ1 channels, which are strongly expressed in epithelial cells or cardiomyocytes......, and KCNQ4 channels, expressed in hair cells and the auditory tract, are tightly regulated by small cell volume changes when co-expressed with aquaporin 1 water-channels (AQP1) in Xenopus oocytes. The KCNQ1 and KCNQ4 current amplitudes precisely reflect the volume of the oocytes. By contrast, the related...... KCNQ2 and KCNQ3 channels, which are prominently expressed in neurons, are insensitive to cell volume changes. The sensitivity of the KCNQ1 and KCNQ4 channels to cell volume changes is independent of the presence of the auxiliary KCNE1-3 subunits, although modulated by KCNE1 in the case of KCNQ1...

  19. White matter volume changes in people who develop psychosis.

    Science.gov (United States)

    Walterfang, Mark; McGuire, Philip K; Yung, Alison R; Phillips, Lisa J; Velakoulis, Dennis; Wood, Stephen J; Suckling, John; Bullmore, Edward T; Brewer, Warrick; Soulsby, Bridget; Desmond, Patricia; McGorry, Patrick D; Pantelis, Christos

    2008-09-01

    Grey matter changes have been described in individuals who are pre- and peri-psychotic, but it is unclear if these changes are accompanied by changes in white matter structures. To determine whether changes in white matter occur prior to and with the transition to psychosis in individuals who are pre-psychotic who had previously demonstrated grey matter reductions in frontotemporal regions. We used magnetic resonance imaging (MRI) to examine regional white matter volume in 75 people with prodromal symptoms. A subset of the original group (n=21) were rescanned at 12-18 months to determine white matter volume changes. Participants were retrospectively categorised according to whether they had or had not developed psychosis at follow-up. Comparison of the baseline MRI data from these two subgroups revealed that individuals who later developed psychosis had larger volumes of white matter in the frontal lobe, particularly in the left hemisphere. Longitudinal comparison of data in individuals who developed psychosis revealed a reduction in white matter volume in the region of the left fronto-occipital fasciculus. Participants who had not developed psychosis showed no reductions in white matter volume but increases in a region subjacent to the right inferior parietal lobule. The reduction in volume of white matter near the left fronto-occipital fasciculus may reflect a change in this tract in association with the onset of frank psychosis.

  20. Classification of male lower torso for underwear design

    Science.gov (United States)

    Cheng, Z.; Kuzmichev, V. E.

    2017-10-01

    By means of scanning technology we have got new information about the morphology of male bodies and have redistricted the classification of men’s underwear by adopting one to consumer demands. To build the new classification in accordance with male body characteristic factors of lower torso, we make the method of underwear designing which allow to get the accurate and convenience for consumers products.

  1. Estimating neuromuscular stimulation within the human torso with Taser stimulus.

    Science.gov (United States)

    Sun, Hongyu; Webster, John G

    2007-11-07

    Designers of electromuscular incapacitation devices need to know efficacy. Which areas of nerve and muscle are stimulated and are these areas adequate to cause incapacitation? This paper focuses on efficacy, which used a torso-sized finite element model with a mesh of about 5 mm. To estimate the neuromuscular regions stimulated by the Taser X26, calculations of electric current density and field strength values with 1 A inserted into the torso using the Utah 3D mesh were made. Field-times-duration values for given Taser stimulation were calculated. Then the region where the motor nerve was stimulated by the Taser was estimated by using a field-times-duration threshold from Reilly (1998 'Applied Bioelectricity: From Electrical Stimulation to Electropathology ' (New York: Springer)). Neuromuscular stimulation occurred up to about 19 cm away from the darts and included the spinal cord. The current density at the heart for dart separation less than 10 cm was smaller than for larger dart separation. Users of finite element computer models will find information for torso models and their creation, meshing and operation.

  2. Change in brain and lesion volumes after CEE therapies

    Science.gov (United States)

    Espeland, Mark A.; Hogan, Patricia E.; Resnick, Susan M.; Bryan, R. Nick; Robinson, Jennifer G.; Goveas, Joseph S.; Davatzikos, Christos; Kuller, Lewis H.; Williamson, Jeff D.; Bushnell, Cheryl D.; Shumaker, Sally A.

    2014-01-01

    Objectives: To determine whether smaller brain volumes in older women who had completed Women's Health Initiative (WHI)-assigned conjugated equine estrogen–based hormone therapy (HT), reported by WHI Memory Study (WHIMS)-MRI, correspond to a continuing increased rate of atrophy an average of 6.1 to 7.7 years later in WHIMS-MRI2. Methods: A total of 1,230 WHI participants were contacted: 797 (64.8%) consented, and 729 (59%) were rescanned an average of 4.7 years after the initial MRI scan. Mean annual rates of change in total brain volume, the primary outcome, and rates of change in ischemic lesion volumes, the secondary outcome, were compared between treatment groups using mixed-effect models with adjustment for trial, clinical site, age, intracranial volumes, and time between MRI measures. Results: Total brain volume decreased an average of 3.22 cm3/y in the active arm and 3.07 cm3/y in the placebo arm (p = 0.53). Total ischemic lesion volumes increased in both arms at a rate of 0.12 cm3/y (p = 0.88). Conclusions: Conjugated equine estrogen–based postmenopausal HT, previously assigned at WHI baseline, did not affect rates of decline in brain volumes or increases in brain lesion volumes during the 4.7 years between the initial and follow-up WHIMS-MRI studies. Smaller frontal lobe volumes were observed as persistent group differences among women assigned to active HT compared with placebo. Women with a history of cardiovascular disease treated with active HT, compared with placebo, had higher rates of accumulation in white matter lesion volume and total brain lesion volume. Further study may elucidate mechanisms that explain these findings. PMID:24384646

  3. Change in Seroma Volume During Whole-Breast Radiation Therapy

    International Nuclear Information System (INIS)

    Sharma, Rajiv; Spierer, Marnee; Mutyala, Subhakar; Thawani, Nitika; Cohen, Hillel W.; Hong, Linda; Garg, Madhur K.; Kalnicki, Shalom

    2009-01-01

    Purpose: After breast-conserving surgery, a seroma often forms in the surgical cavity. If not drained, it may affect the volume of tumor bed requiring a boost after whole-breast radiation therapy (WBRT). Our objective was to evaluate the change in seroma volume that occurs during WBRT, before boost planning. Methods and Materials: A retrospective review was performed of women receiving breast-conserving therapy with evidence of seroma at the time of WBRT planning. Computed tomography (CT) simulation was performed before WBRT and before the tumor bed boost. All patients received either a hypofractionated (42.4 Gy/16 fraction + 9.6 Gy/4 fraction boost) or standard fractionated (50.4 Gy/28 fraction + 10 Gy/5 fraction boost) regimen. Seroma volumes were contoured and compared on CT at the time of WBRT simulation and tumor bed boost planning. Results: Twenty-four patients with evidence of seroma were identified and all patients received WBRT without drainage of the seroma. Mean seroma volume before WBRT and at boost planning were significantly different at 65.7 cm 3 (SD, 50.5 cm 3 ) and 35.6 cm 3 (SD, 24.8 cm 3 ), respectively (p < 0.001). Mean and median reduction in seroma volume during radiation were 39.6% (SD, 23.8%) and 46.2% (range, 10.7-76.7%), respectively. Fractionation schedule was not correlated with change in seroma volume. Length of time from surgery to start of radiation therapy showed an inverse correlation with change in seroma volume (Pearson correlation r = -0.53, p < 0.01). Conclusions: The volume of seroma changes significantly during WBRT. Consequently, the accuracy of breast boost planning is likely affected, as is the volume of normal breast tissue irradiated. CT-based boost planning before boost irradiation is suggested to ensure appropriate coverage.

  4. Changes of pituitary gland volume in Kennedy disease.

    Science.gov (United States)

    Pieper, C C; Teismann, I K; Konrad, C; Heindel, W L; Schiffbauer, H

    2013-12-01

    Kennedy disease is a rare X-linked neurodegenerative disorder caused by a CAG repeat expansion in the first exon of the androgen-receptor gene. Apart from neurologic signs, this mutation can cause a partial androgen insensitivity syndrome with typical alterations of gonadotropic hormones produced by the pituitary gland. The aim of the present study was therefore to evaluate the impact of Kennedy disease on pituitary gland volume under the hypothesis that endocrinologic changes caused by partial androgen insensitivity may lead to morphologic changes (ie, hypertrophy) of the pituitary gland. Pituitary gland volume was measured in sagittal sections of 3D T1-weighted 3T-MR imaging data of 8 patients with genetically proven Kennedy disease and compared with 16 healthy age-matched control subjects by use of Multitracer by a blinded, experienced radiologist. The results were analyzed by a univariant ANOVA with total brain volume as a covariant. Furthermore, correlation and linear regression analyses were performed for pituitary volume, patient age, disease duration, and CAG repeat expansion length. Intraobserver reliability was evaluated by means of the Pearson correlation coefficient. Pituitary volume was significantly larger in patients with Kennedy disease (636 [±90] mm(3)) than in healthy control subjects (534 [±91] mm(3)) (P = .041). There was no significant difference in total brain volume (P = .379). Control subjects showed a significant decrease in volume with age (r = -0.712, P = .002), whereas there was a trend to increasing gland volume in patients with Kennedy disease (r = 0.443, P = .272). Gland volume correlated with CAG repeat expansion length in patients (r = 0.630, P = .047). The correlation coefficient for intraobserver reliability was 0.94 (P pituitary volume that correlated with the CAG repeat expansion length. This could reflect hypertrophy as the result of elevated gonadotropic hormone secretion caused by the androgen receptor mutation with partial

  5. Environmental law and climate change : Volumes I & II

    NARCIS (Netherlands)

    Verschuuren, Jonathan

    Two volume set that brings together 54 of the most influential and important scientific journal articles in the field of climate law, thematically grouped together as follows: introducing climate law, theories and approaches, climate change mitigation, climate change adaptation, climate justice,

  6. Epidural anesthesia, hypotension, and changes in intravascular volume

    DEFF Research Database (Denmark)

    Holte, Kathrine; Foss, Nicolai B; Svensén, Christer

    2004-01-01

    receiving hydroxyethyl starch. RESULTS: Plasma volume did not change per se after thoracic epidural anesthesia despite a decrease in blood pressure. Plasma volume increased with fluid administration but remained unchanged with vasopressors despite that both treatments had similar hemodynamic effects...... constant was 56 ml/min. CONCLUSIONS: Thoracic epidural anesthesia per se does not lead to changes in blood volumes despite a reduction in blood pressure. When fluid is infused, there is a dilution, and the fluid initially seems to be located centrally. Because administration of hydroxyethyl starch......BACKGROUND: The most common side effect of epidural or spinal anesthesia is hypotension with functional hypovolemia prompting fluid infusions or administration of vasopressors. Short-term studies (20 min) in patients undergoing lumbar epidural anesthesia suggest that plasma volume may increase when...

  7. Pituitary volumes are changed in patients with conversion disorder.

    Science.gov (United States)

    Atmaca, Murad; Baykara, Sema; Mermi, Osman; Yildirim, Hanefi; Akaslan, Unsal

    2016-03-01

    Our study group previously measured pituitary volumes and found a relationship between somatoform disoders and pituitary volumes. Therefore, in conversion disorder, another somatoform disorder, we hypothesized that pituitary gland volumes would be reduced. Twenty female patients and healthy controls were recruited to the present investigation. The volumes of the pituitary gland were determined by using a 1.5 Tesla magnetic resonance scanner. We found that the pituitary gland volumes of the patients with conversion disorder were significantly smaller than those of healthy control subjects. In the patients with conversion disorder but not in the healthy control group, a significant negative correlation between the duration of illness and pituitary gland volume was determined. In summary, in the present study, we suggest that the patients with conversion disorder have smaller pituitary volumes compared to those of healthy control subjects. Further studies should confirm our data and ascertain whether volumetric alterations determined in the patients with conversion disorder can be changed with treatment or if they change over time.

  8. Change of the human taste bud volume over time.

    Science.gov (United States)

    Srur, Ehab; Stachs, Oliver; Guthoff, Rudolf; Witt, Martin; Pau, Hans Wilhelm; Just, Tino

    2010-08-01

    The specific aim of this study is to measure the taste volume in healthy human subjects over a 2.5-month period and to demonstrate morphological changes of the peripheral taste organs. Eighteen human taste buds in four fungiform papillae (fPap) were examined over a 10-week period. The fungiform papillae investigated were selected based on the form of the papillae or the arrangement of surface taste pores. Measurements were performed over 10 consecutive weeks, with five scans in a day once a week. The following parameters were measured: height and diameter of the taste bud, diameter of the fungiform papilla and diameter of the taste pore. The findings of this exploratory study indicated that (1) taste bud volumes changed over a 10-week period, (2) the interval between two volume maxima within the 10-week period was 3-5 weeks, and (3) the diameter of the fPap did not correlate with the volume of a single taste bud or with the volume of all taste buds in the fPap within the 10-week period. This exploratory in vivo study revealed changes in taste bud volumes in healthy humans with age-related gustatory sensitivity. These findings need to be considered when studying the effect of denervation of fungiform papillae in vivo using confocal microscopy. Crown Copyright 2009. Published by Elsevier Ireland Ltd. All rights reserved.

  9. Measurement of cell volume changes by fluorescence self-quenching

    DEFF Research Database (Denmark)

    Hamann, Steffen; Kiilgaard, J.F.; Litman, Thomas

    2002-01-01

    At high concentrations, certain fluorophores undergo self-quenching, i.e., fluorescence intensity decreases with increasing fluorophore concentration. Accordingly, the self-quenching properties can be used for measuring water volume changes in lipid vesicles. In cells, quantitative determination...... concentrations of the fluorophore calcein suitable for measurement of changes in cell water volume by self-quenching. The relationship between calcein fluorescence intensity, when excited at 490 nm (its excitation maximum), and calcein concentration was investigated in vitro and in various cultured cell types...... to a decrease in calcein fluorescence with high signal-to-noise ratio (>15). Similar results were obtained with the fluorophore BCECF when excited at its isosbestic wavelength (436 nm). The present results demonstrate the usefulness of fluorescence self-quenching to measure rapid changes in cell water volume....

  10. ICP curve morphology and intracranial flow-volume changes

    DEFF Research Database (Denmark)

    Unnerbäck, Mårten; Ottesen, Johnny T.; Reinstrup, Peter

    2018-01-01

    proposed to shape the ICP curve. This study tested the hypothesis that the ICP curve correlates to intracranial volume changes. METHODS: Cine phase contrast magnetic resonance imaging (MRI) examinations were performed in neuro-intensive care patients with simultaneous ICP monitoring. The MRI was set......BACKGROUND: The intracranial pressure (ICP) curve with its different peaks has been extensively studied, but the exact physiological mechanisms behind its morphology are still not fully understood. Both intracranial volume change (ΔICV) and transmission of the arterial blood pressure have been...

  11. Early changes in left atrial volume after acute myocardial infarction

    DEFF Research Database (Denmark)

    Bakkestrom, R.; Andersen, Mads J; Ersboll, M.

    2016-01-01

    . The objective was to assess changes in LA volume early after MI in patients with diastolic dysfunction and the relation to invasive hemodynamics and natriuretic peptides. Methods: 62 patients with left ventricle ejection fraction (LVEF) >= 45%, diastolic E/e' > 8 and LA volume index >34 ml/m(2) within 48 h......Background: Dilatation of left atrium (LA) reflects chronic LA pressure or volume overload that possesses considerable prognostic information. Little is known regarding the interaction between LA remodeling after acute myocardial infarction (MI) and left atrial pressure at rest and during exercise...... of MI were enrolled. After 1 and 4 months blood sampling, echocardiography and right heart catheterization were performed during exercise test. Results: LA remodeling was considered in patients with a change from mild (35-41 ml/m(2)), to severe (>48ml/m(2)) dilatation after 4 months (Found in 22...

  12. Changes in olfactory bulb volume following lateralized olfactory training.

    Science.gov (United States)

    Negoias, S; Pietsch, K; Hummel, T

    2017-08-01

    Repeated exposure to odors modifies olfactory function. Consequently, "olfactory training" plays a significant role in hyposmia treatment. In addition, numerous studies show that the olfactory bulb (OB) volume changes in disorders associated with olfactory dysfunction. Aim of this study was to investigate whether and how olfactory bulb volume changes in relation to lateralized olfactory training in healthy people. Over a period of 4 months, 97 healthy participants (63 females and 34 males, mean age: 23.74 ± 4.16 years, age range: 19-43 years) performed olfactory training by exposing the same nostril twice a day to 4 odors (lemon, rose, eucalyptus and cloves) while closing the other nostril. Before and after olfactory training, magnetic resonance imaging (MRI) scans were performed to measure OB volume. Furthermore, participants underwent lateralized odor threshold and odor identification testing using the "Sniffin' Sticks" test battery.OB volume increased significantly after olfactory training (11.3 % and 13.1 % respectively) for both trained and untrained nostril. No significant effects of sex, duration and frequency of training or age of the subjects were seen. Interestingly, PEA odor thresholds worsened after training, while olfactory identification remained unchanged.These data show for the first time in humans that olfactory training may involve top-down process, which ultimately lead to a bilateral increase in olfactory bulb volume.

  13. Changes in atheroma volume estimated from digitized femoral arteriograms

    International Nuclear Information System (INIS)

    Nilsson, S.; Erikson, U.

    1990-01-01

    To evaluate the effects of treatment in patients with cardiovascular risk factors, valid and reproducible methods for assessing changes in atheroma volume are required. We postulated that these changes could be accurately estimated by repeat measurement of the lumen volume of the artery to be studied. With a computer-based technique, the lumen volume of a 20 cm segment of the femoral artery was measured in arteriograms from 107 patients with hypercholesterolemia. Films were digitized with use of a high-resolution scanner, cross-sectional areas were calculated with a slice thickness of 150 μm and the lumen volume was obtained by their integration. The validity of the method was demonstrated in model experiments. An automatic algorithm to correct for changes due to patient positioning was developed and validated in a model experiment. With repeat measurment 10 min and 11 to 13 months apart the coefficients of variation were 2.9% (N=107) and 6.1% (N=29), respectively. (orig.)

  14. A longitudinal study of brain volume changes in normal aging

    Energy Technology Data Exchange (ETDEWEB)

    Takao, Hidemasa, E-mail: takaoh-tky@umin.ac.jp [Department of Radiology, Graduate School of Medicine, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8655 (Japan); Hayashi, Naoto [Department of Computational Diagnostic Radiology and Preventive Medicine, Graduate School of Medicine, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8655 (Japan); Ohtomo, Kuni [Department of Radiology, Graduate School of Medicine, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8655 (Japan)

    2012-10-15

    Purpose: To evaluate the effect of normal aging on brain volumes and examine the effects of age and sex on the rates of changes in global and regional brain volumes. Methods: A total of 199 normal subjects (65 females and 134 males, mean age = 56.4 ± 9.9 years, age range = 38.1–82.9 years) were included in this study. Each subject was scanned twice, at an interval of about 2 years (range = 1.5–2.3 years). Two-time-point percentage brain volume change (PBVC) was estimated with SIENA 2.6. Results: The mean annualized PBVC was −0.23%/y. Analysis of covariance (ANCOVA) for annual brain volume changes revealed a main effect of age. There was no main effect of sex, nor was there a sex-by-age interaction. Voxel-wise analysis revealed a negative correlation between age and edge displacement values mainly in the periventricular region. Conclusions: The results of our study indicate that brain atrophy accelerates with increasing age and that there is no gender difference in the rate of brain atrophy.

  15. A longitudinal study of brain volume changes in normal aging

    International Nuclear Information System (INIS)

    Takao, Hidemasa; Hayashi, Naoto; Ohtomo, Kuni

    2012-01-01

    Purpose: To evaluate the effect of normal aging on brain volumes and examine the effects of age and sex on the rates of changes in global and regional brain volumes. Methods: A total of 199 normal subjects (65 females and 134 males, mean age = 56.4 ± 9.9 years, age range = 38.1–82.9 years) were included in this study. Each subject was scanned twice, at an interval of about 2 years (range = 1.5–2.3 years). Two-time-point percentage brain volume change (PBVC) was estimated with SIENA 2.6. Results: The mean annualized PBVC was −0.23%/y. Analysis of covariance (ANCOVA) for annual brain volume changes revealed a main effect of age. There was no main effect of sex, nor was there a sex-by-age interaction. Voxel-wise analysis revealed a negative correlation between age and edge displacement values mainly in the periventricular region. Conclusions: The results of our study indicate that brain atrophy accelerates with increasing age and that there is no gender difference in the rate of brain atrophy

  16. Changes in Upper Airway Volume Following Orthognathic Surgery.

    Science.gov (United States)

    Marcussen, Lillian; Stokbro, Kasper; Aagaard, Esben; Torkov, Peter; Thygesen, Torben

    2017-01-01

    Reduced volume of the internal skeletal dimensions of the face is 1 of the main causes of obstructive sleep apnea, and attention to patients' airways is necessary when planning orthognathic treatment. This study aims to describe changes in upper airway volume following virtually planned orthognathic surgery.A retrospective pilot study was designed with 30 randomly selected patients (10 men and 20 women, aged 23.1 ± 6.8 years, molar-relations: 15 neutral, 8 distal, and 7 mesial). Cone-beam computed tomography scans were performed before surgery and 1 week following surgery. The authors did total upper airway volume measurements and obtained 1-mm slices at vertical levels in the velo-, oro-, and hypopharynx and at the smallest visible cross-section.Measurements before and after surgery were compared using Student t test.After orthognathic surgery, the minimum cross-sectional area at the vertical level increased from 83 mm ± 33 before surgery to 102 mm ± 36 after surgery (P = 0.019). In patients with neutral and distal occlusions, the minimum cross-sectional slice volume increased in 87% but in only 57% with mesial occlusion.The present findings suggest that orthognathic surgery increases upper airway volume parameters, but a few patients have continued impairment of the airways following orthognathic surgery. Further studies are needed to confirm an individual surgical planning approach that potentially could bring the minimum cross sectional area out of the risk zone.

  17. Changes in taste bud volume during taste disturbance.

    Science.gov (United States)

    Srur, Ehab; Pau, Hans Wilhelm; Just, Tino

    2011-08-01

    On-line mapping and serial volume measurements of taste buds with confocal laser scanning microscopy provide information on the peripheral gustatory organ over time. We report the volumetric measurements of four selected fungiform papillae over 8 weeks in a 62-year-old man with taste disturbance, which was more apparent on the right than on the left side. In the two papillae on the right side, no taste buds were detected within the fungiform papillae in the sixth and eighth week. During sixth and eighth week, there was no response to the highest presented stimuli in electrogustometry (1 mA) on the right-sided tongue tip nor at the tongue edge. The morphology (shape, diameter) of the fungiform papillae on both sides remained unchanged. Comparison of the time course of the volume changes revealed differences corresponding to gustatory sensitivity. These findings suggest that the time course of volume changes indicated taste disturbance in our patient, rather than morphological changes in the fungiform papillae. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

  18. Implications of changing scattering properties on Greenland ice sheet volume change from Cryosat-2 altimetry

    DEFF Research Database (Denmark)

    Simonsen, Sebastian Bjerregaard; Sørensen, Louise Sandberg

    2017-01-01

    ) in the elevation change algorithm, to correct for temporal changes in the ratio between surface- and volume-scatter in Cryosat-2 observations. We present elevation and volume changes for the Greenland ice sheet in the period from 2010 until 2014. The waveform parameters considered here are the backscatter...... waveform parameters to be applicable for correcting for changes in volume scattering. The best results in the Synthetic Aperture Radar Interferometric mode area of the GrIS are found when applying only the backscatter correction, whereas the best result in the Low Resolution Mode area is obtained by only......Long-term observations of surface elevation change of the Greenland ice sheet (GrIS) is of utmost importance when assessing the state of the ice sheet. Satellite radar altimetry offers a long time series of data over the GrIS, starting with ERS-1 in 1991. ESA's Cryosat-2 mission, launched in 2010...

  19. Changes in plasma volume and baroreflex function following resistance exercise

    Science.gov (United States)

    Ploutz, L. L.; Tatro, D. L.; Dudley, G. A.; Convertino, V. A.

    1993-01-01

    The dynamics of change in plasma volume (PV) and baroreflex responses have been reported over 24 h immediately following maximal cycle exercise. The purpose of this study was to determine if PV and baroreflex showed similar changes for 24 h after resistance exercise. Eight men were studied on 2 test days, 1 week apart. On 1 day, per cent change (% delta) in PV was estimated at 0,3, and 6 h after resistance exercise using haematocrit and haemoglobin. Baseline PV was measured 24 h after exercise using Evans blue dye. The carotid baroreceptor-cardiac reflex response was measured before, and 3, 6, 9, 12, and 24 h post-exercise. Each subject performed six sets of the bench press and leg press with 10 repetitions per set with a load that induced failure within each set. On a control day, the protocol was used without exercise. Plasma volume did not change during the control day. There was a 20% decrease in PV immediately post-exercise; the recovery of the PV was rapid and complete within 3 h. PV was 20% greater 24 h post-exercise than on the control day. There were no differences in any of the baroreflex measurements. Therefore, it is suggested that PV shifts may occur without altering baroreflex sensitivity.

  20. Thermal volume changes in clays and clay-stones

    International Nuclear Information System (INIS)

    Delage, P.; Sulem, J.; Mohajerani, M.; Tang, A.M.; Monfared, M.

    2012-01-01

    Document available in extended abstract form only. The disposal of high activity exothermic radioactive waste at great depth in clay host rocks will induce a temperature elevation that has been investigated in various underground research laboratories in Belgium, France and Switzerland through in-situ tests. Thermal effects are better known in clays (in particular Boom clay) than in clay-stone (e.g. Opalinus clay and Callovo-Oxfordian clay-stone). In terms of volume changes, Figure 1 confirms the findings of Hueckel and Baldi (1990) that volume changes depend on the over-consolidation ratio (OCR) of the clay. In drained conditions, normally consolidated clays exhibit plastic contraction when heated, whereas over-consolidated clay exhibit elastic dilation. The nature of thermal volume changes in heated clays obviously has a significant effect on thermally induced pore pressures, when drainage is not instantaneous like what occurs in-situ. Compared to clays, the thermal volume change behaviour of clay-stones is less well known than that of clays. clay-stone are a priori suspected to behave like over-consolidated clays. In this paper, a comparison of recent results obtained in the laboratory on the drained thermal volume changes of clay-stones is presented and discussed. It is difficult to run drained mechanical tests in clay-stones like the Opalinus clay and the Callovo-Oxfordian clay-stone because of their quite low permeability (10 -12 - 10 -13 m/s). This also holds true for thermal tests. Due to the significant difference in thermal expansion coefficient between minerals and water, it is necessary to adopt very slow heating rate (0.5 - 1 C/h) to avoid any thermal pressurization. To do so, a new hollow cylinder apparatus (100 mm external diameter, 60 mm internal diameter) with lateral drainages reducing the drainage length to half the sample thickness (10 mm) has been developed (Monfared et al. 2011). The results of a drained cyclic thermal test carried out on

  1. Human torso phantom for imaging of heart with realistic modes of cardiac and respiratory motion

    Science.gov (United States)

    Boutchko, Rostyslav; Balakrishnan, Karthikayan; Gullberg, Grant T; O& #x27; Neil, James P

    2013-09-17

    A human torso phantom and its construction, wherein the phantom mimics respiratory and cardiac cycles in a human allowing acquisition of medical imaging data under conditions simulating patient cardiac and respiratory motion.

  2. Beach Volume Change Using Uav Photogrammetry Songjung Beach, Korea

    Science.gov (United States)

    Yoo, C. I.; Oh, T. S.

    2016-06-01

    Natural beach is controlled by many factors related to wave and tidal forces, wind, sediment, and initial topography. For this reason, if numerous topographic data of beach is accurately collected, coastal erosion/acceleration is able to be assessed and clarified. Generally, however, many studies on coastal erosion have limitation to analyse the whole beach, carried out of partial area as like shoreline (horizontal 2D) and beach profile (vertical 2D) on account of limitation of numerical simulation. This is an important application for prevention of coastal erosion, and UAV photogrammetry is also used to 3D topographic data. This paper analyses the use of unmanned aerial vehicles (UAV) to 3D map and beach volume change. UAV (Quadcopter) equipped with a non-metric camera was used to acquire images in Songjung beach which is located south-east Korea peninsula. The dynamics of beach topography, its geometric properties and estimates of eroded and deposited sand volumes were determined by combining elevation data with quarterly RTK-VRS measurements. To explore the new possibilities for assessment of coastal change we have developed a methodology for 3D analysis of coastal topography evolution based on existing high resolution elevation data combined with low coast, UAV and on-ground RTK-VRS surveys. DSMs were obtained by stereo-matching using Agisoft Photoscan. Using GCPs the vertical accuracy of the DSMs was found to be 10 cm or better. The resulting datasets were integrated in a local coordinates and the method proved to be a very useful fool for the detection of areas where coastal erosion occurs and for the quantification of beach change. The value of such analysis is illustrated by applications to coastal of South Korea sites that face significant management challenges.

  3. BEACH VOLUME CHANGE USING UAV PHOTOGRAMMETRY SONGJUNG BEACH, KOREA

    Directory of Open Access Journals (Sweden)

    C. I. Yoo

    2016-06-01

    Full Text Available Natural beach is controlled by many factors related to wave and tidal forces, wind, sediment, and initial topography. For this reason, if numerous topographic data of beach is accurately collected, coastal erosion/acceleration is able to be assessed and clarified. Generally, however, many studies on coastal erosion have limitation to analyse the whole beach, carried out of partial area as like shoreline (horizontal 2D and beach profile (vertical 2D on account of limitation of numerical simulation. This is an important application for prevention of coastal erosion, and UAV photogrammetry is also used to 3D topographic data. This paper analyses the use of unmanned aerial vehicles (UAV to 3D map and beach volume change. UAV (Quadcopter equipped with a non-metric camera was used to acquire images in Songjung beach which is located south-east Korea peninsula. The dynamics of beach topography, its geometric properties and estimates of eroded and deposited sand volumes were determined by combining elevation data with quarterly RTK-VRS measurements. To explore the new possibilities for assessment of coastal change we have developed a methodology for 3D analysis of coastal topography evolution based on existing high resolution elevation data combined with low coast, UAV and on-ground RTK-VRS surveys. DSMs were obtained by stereo-matching using Agisoft Photoscan. Using GCPs the vertical accuracy of the DSMs was found to be 10 cm or better. The resulting datasets were integrated in a local coordinates and the method proved to be a very useful fool for the detection of areas where coastal erosion occurs and for the quantification of beach change. The value of such analysis is illustrated by applications to coastal of South Korea sites that face significant management challenges.

  4. A Monte Carlo Simulation of the in vivo measurement of lung activity in the Lawrence Livermore National Laboratory torso phantom.

    Science.gov (United States)

    Acha, Robert; Brey, Richard; Capello, Kevin

    2013-02-01

    A torso phantom was developed by the Lawrence Livermore National Laboratory (LLNL) that serves as a standard for intercomparison and intercalibration of detector systems used to measure low-energy photons from radionuclides, such as americium deposited in the lungs. DICOM images of the second-generation Human Monitoring Laboratory-Lawrence Livermore National Laboratory (HML-LLNL) torso phantom were segmented and converted into three-dimensional (3D) voxel phantoms to simulate the response of high purity germanium (HPGe) detector systems, as found in the HML new lung counter using a Monte Carlo technique. The photon energies of interest in this study were 17.5, 26.4, 45.4, 59.5, 122, 244, and 344 keV. The detection efficiencies at these photon energies were predicted for different chest wall thicknesses (1.49 to 6.35 cm) and compared to measured values obtained with lungs containing (241)Am (34.8 kBq) and (152)Eu (10.4 kBq). It was observed that no statistically significant differences exist at the 95% confidence level between the mean values of simulated and measured detection efficiencies. Comparisons between the simulated and measured detection efficiencies reveal a variation of 20% at 17.5 keV and 1% at 59.5 keV. It was found that small changes in the formulation of the tissue substitute material caused no significant change in the outcome of Monte Carlo simulations.

  5. Remote sensing for global change, climate change and atmosphere and ocean forecasting. Volume 1

    International Nuclear Information System (INIS)

    1992-01-01

    This volume is separated in three sessions. First part is on remote sensing for global change (with global modelling, land cover change on global scale, ocean colour studies of marine biosphere, biological and hydrological interactions and large scale experiments). Second part is on remote sensing for climate change (with earth radiation and clouds, sea ice, global climate research programme). Third part is on remote sensing for atmosphere and ocean forecasting (with temperatures and humidity, winds, data assimilation, cloud imagery, sea surface temperature, ocean waves and topography). (A.B.). refs., figs., tabs

  6. Baroreflex Responses to Acute Changes in Blood Volume in Humans

    Science.gov (United States)

    Thompson, Cynthia A.; Tatro, Dana L.; Ludwig, David A.; Convertino, Victor A.

    1990-01-01

    To test the hypothesis that acute changes in plasma volume affect the stimulus-response relations of high- and low- pressure baroreflexes, eight men (27-44 yr old) underwent measurements for carotid-cardiac and cardiopulmonary baro-reflex responses under the following three volemic conditions: hypovolemic, normovolemic, and hypervolemic. The stimulus- response relation of the carotid-cardiac response curve was generated using a neck cuff device, which delivered pressure changes between +40 and -65 mmHg in continuous steps of 15 mmHg. The stimulus-response relationship, of the cardio-pulmonary baroreflex were studied by measurements of Forearm Vascular Resistance (FVR) and Peripheral Venous Pressure (PVP) during low levels of lower body negative pressure (O to -20 mmHg). The results indicate greater demand for vasoconstriction for equal reductions in venous pressure during progressive hypovolemia; this condition may compromise the capacity to provide adequate peripheral resistance during severe orthostatic stress. Fluid loading before reentry after spaceflight may act to restore vasoconstrictive capacity of the cardiopulmonary baroreflex but may not be an effective countermeasure against potential post- flight impairment of the carotid-cardiac baroreflex.

  7. Theoretical study for volume changes associated with the helix-coil transition of peptides.

    Science.gov (United States)

    Imai, T; Harano, Y; Kovalenko, A; Hirata, F

    2001-12-01

    We calculate the partial molar volumes and their changes associated with the coil(extended)-to-helix transition of two types of peptide, glycine-oligomer and glutamic acid-oligomer, in aqueous solutions by using the Kirkwood-Buff solution theory coupled with the three-dimensional reference interaction site model (3D-RISM) theory. The volume changes associated with the transition are small and positive. The volume is analyzed by decomposing it into five contributions following the procedure proposed by Chalikian and Breslauer: the ideal volume, the van der Waals volume, the void volume, the thermal volume, and the interaction volume. The ideal volumes and the van der Waals volumes do not change appreciably upon the transition. In the both cases of glycine-peptide and glutamic acid-peptide, the changes in the void volumes are positive, while those in the thermal volumes are negative, and tend to balance those in the void volumes. The change in the interaction volume of glycine-peptide does not significantly contribute, while that of glutamic acid-peptide makes a negative contribution. Copyright 2001 John Wiley & Sons, Inc. Biopolymers 59: 512-519, 2001

  8. Change in tidal volume during cardiopulmonary resuscitation in newborn piglets.

    Science.gov (United States)

    Li, Elliott S; Cheung, Po-Yin; O'Reilly, Megan; Schmölzer, Georg M

    2015-11-01

    The purpose of inflations during cardiopulmonary resuscitation (CPR) is to deliver an adequate tidal volume (VT) to facilitate gas exchange. However, no study has examined VT delivery during chest compression (CC) in detail to understand the effect of CC on lung aeration. The aim of the study was to examine VT changes during CC and their effect on lung aeration. Piglets were anaesthetised, instrumented and intubated with zero leak. They were then randomly assigned to CPR using either 3:1 compression:ventilation ratio (C:V) (n=6), continuous CC with asynchronous ventilations (CCaV) (90 CC/min with 30/min asynchronous ventilations) (n=6) or continuous CC superimposed with 30 s sustained inflations (CC+SI) with a CC rate of 120/min (n=5). A respiratory function monitor (NM3, Respironics, Philips, Andover, Massachusetts, USA) was used to continuously measure inspiration tidal volume (VTi) and expirational tidal volume (VTe). ANOVA with Bonferroni post-test were used to compare variables of all three groups. During the inflation in the 3:1 C:V group, the mean (SD) VTi and VTe was 23.5 (5.3) mL/kg and 19.4 (2.7) mL/kg (p=0.16), respectively. During the CC, we observed a significant VT loss in the 3:1 group with VTi and VTe being 4.1 (1.2) mL/kg and 11.1 (3.3) mL/kg (p=0.007), respectively. In the CCaV group, VTe was higher compared with VTi, but this was not significant. In the CC+SI group, a VT gain during each CC with VTi and VTe of 16.3 (3.2) mL/kg and 14 (3) mL/kg (p=0.21), respectively, was observed. VT delivery is improved using CC+SI compared with 3:1 C:V. This improvement in VT delivery may lead to better alveolar oxygen delivery and lung aeration. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

  9. Breathing, Laughing, Sneezing, Coughing: Model and Control of an Anatomically Inspired, Physically-Based Human Torso Simulation

    OpenAIRE

    DiLorenzo, Paul Carmen

    2008-01-01

    Breathing, laughing, sneezing and coughing are all important human behaviors that are generated in the torso. Yet, when these behaviors are animated, the movement of the human torso is often simplified and stylized. Recent work aiming to depict the movement of the torso has focused on pure data-driven approaches such as a skin capture of an actor using a motion capture system. Although this generates impressive results to recreate the captured motion, it does not provide control to an animato...

  10. Longitudinal Changes in Total Brain Volume in Schizophrenia: Relation to Symptom Severity, Cognition and Antipsychotic Medication

    NARCIS (Netherlands)

    Veijola, J.; Guo, J.Y.; Moilanen, J.S.; Jaaskelainen, E.; Miettunen, J.; Kyllonen, M.; Haapea, M.; Huhtaniska, S.; Alaraisanen, A.; Maki, P.; Kiviniemi, V.; Nikkinen, J.; Starck, T.; Remes, J.J.; Tanskanen, P.; Tervonen, O.; Wink, A.M.; Kehagia, A.; Suckling, J.; Kobayashi, H.; Barnett, J.H.; Barnes, A.; Koponen, H.J.; Jones, P.B.; Isohanni, M.; Murray, G.K.

    2014-01-01

    Studies show evidence of longitudinal brain volume decreases in schizophrenia. We studied brain volume changes and their relation to symptom severity, level of function, cognition, and antipsychotic medication in participants with schizophrenia and control participants from a general population

  11. Orthostatic leg blood volume changes assessed by near-infrared spectroscopy

    DEFF Research Database (Denmark)

    Truijen, J; Kim, Y S; Krediet, C T P

    2012-01-01

    posture, volume accumulation in small blood vessels contributes significantly to the total fluid volume accumulated in the legs. Considering that near-infrared spectroscopy (NIRS) tracks postural blood volume changes within the small blood vessels of the lower leg, we evaluated the NIRS-determined changes......-linear accumulation of blood volume in the small vessels of the leg, with an initial fast phase followed by a more gradual increase at least partly contributing to the relocation of fluid during orthostatic stress....

  12. Factors influencing liver and spleen volume changes after donor hepatectomy for living donor liver transplantation

    Energy Technology Data Exchange (ETDEWEB)

    Bae, Ji Hee; Ryeom, Hunku; Song, Jung Hup [Kyungpook National University Hospital, Daegu (Korea, Republic of)

    2013-11-15

    To define the changes in liver and spleen volumes in the early postoperative period after partial liver donation for living-donor liver transplantation (LDLT) and to determine factors that influence liver and spleen volume changes. 27 donors who underwent partial hepatectomy for LDLT were included in this study. The rates of liver and spleen volume change, measured with CT volumetry, were correlated with several factors. The analyzed factors included the indocyanine green (ICG) retention rate at 15 minutes after ICG administration, preoperative platelet count, preoperative liver and splenic volumes, resected liver volume, resected-to-whole liver volume ratio (LV{sub R}/LV{sub W}), resected liver volume to the sum of whole liver and spleen volume ratio [LV{sub R}/(LV{sub W} + SV{sub 0})], and pre and post hepatectomy portal venous pressures. In all hepatectomy donors, the volumes of the remnant liver and spleen were increased (increased rates, 59.5 ± 50.5%, 47.9 ± 22.6%). The increment rate of the remnant liver volume revealed a positive correlation with LV{sub R}/LV{sub W} (r = 0.759, p < 0.01). The other analyzed factors showed no correlation with changes in liver and spleen volumes. The spleen and remnant liver volumes were increased at CT volumetry performed 2 weeks after partial liver donation. Among the various analyzed factors, LV{sub R}/LV{sub W} influences the increment rate of the remnant liver volume.

  13. Insignificant change in Antarctic snowmelt volume since 1979

    NARCIS (Netherlands)

    Kuipers Munneke, P.; Picard, G.; van den Broeke, M.R.; Lenaerts, J.T.M.; van Meijgaard, E.

    2012-01-01

    Surface snowmelt is widespread in coastal Antarctica. Satellite-based microwave sensors have been observing melt area and duration for over three decades. However, these observations do not reveal the total volume of meltwater produced on the ice sheet. Here we present an Antarctic melt volume

  14. Human choice and climate change. Volume 4: What have we learned?

    International Nuclear Information System (INIS)

    Raynor, S.; Malone, E.

    1998-01-01

    This book is Volume 4 of a four-volume set which assesses social science research that is relevant to global climate change from a wide-ranging interdisciplinary perspective. Attention is focused on lessons learned as related to climate change. This series is indispensable reading for scientists and engineers wishing to make an effective contribution to the climate change policy debate

  15. The Insect Neuropeptide PTTH Activates Receptor Tyrosine Kinase Torso to Initiate Metamorphosis

    DEFF Research Database (Denmark)

    Rewitz, Kim; Yamanaka, Naoki; Gilbert, Lawrence

    2009-01-01

    Holometabolous insects undergo complete metamorphosis to become sexually mature adults. Metamorphosis is initiated by brain-derived prothoracicotropic hormone (PTTH), which stimulates the production of the molting hormone ecdysone via an incompletely defined signaling pathway. Here we demonstrate...... in the prothoracic gland (PG), and its loss phenocopies the removal of PTTH. The activation of Torso by PTTH stimulates extracellular signal–regulated kinase (ERK) phosphorylation, and the loss of ERK in the PG phenocopies the loss of PTTH and Torso. We conclude that PTTH initiates metamorphosis by activation...

  16. Bridge deck concrete volume change : final contract report.

    Science.gov (United States)

    2010-02-01

    Concrete structures such as bridge decks, with large surface area relative to volume, shrink and crack, thus reducing service life performance and increasing operation costs. The project evaluated the early, first 24 hours, and long-term, 180 days, s...

  17. The effect of γ radiation on a change in the volume of Protozoa cells

    International Nuclear Information System (INIS)

    Kalinowska, A.

    1977-01-01

    An investigation was carried out on the effect of various doses of γ radiation on changes in the volume of Spirostomum ambiguum and on the time of return of the volume of this protozoan to the initial state. It was found that γ rays brought about a decrease in the volume of the animal, depending in a linear relation on the dose, while the return of the volume to the initial state is negatively correlated with the received dose. (author)

  18. MODEL PERUBAHAN VOLUME KERIPIK BUAH SELAMA PROSES PENGGORENGAN SECARA VAKUM [Model for Volume Changes in Fruit Chips during Vacuum Frying

    Directory of Open Access Journals (Sweden)

    Jamaluddin1*

    2011-06-01

    Full Text Available Expansion and puffing are specific characteristics of fried products critical for consumer preferences. To obtain expanded and puffed dried products that fit well with consumer acceptance criteria, it is necessary to pay attention to the process conditions which change the raw material characteristics during frying. The important changes include volume and density ratio of the products during frying. Hypothetically, these changes are due to water vaporization and the decrease dry matter in the products. The objective of this research is to develop a mathematical model of volume and density ratio changes for jack fruit during vacuum frying as a function of water and starch content reductions. Samples were vacuum fried at 70–100OC and pressure of 80-90 kPa for 15–60 min. The parameters observed were volume and density as well as water and starch contents of samples before and after vacuum frying. The results showed that the developed model can be used to predict changes in volume and density ratio of jack fruit during vacuum frying.

  19. Symptom dimensions are associated with progressive brain volume changes in schizophrenia

    NARCIS (Netherlands)

    Collin, G.; Derks, E. M.; van Haren, N. E. M.; Schnack, H. G.; Hulshoff Pol, H. E.; Kahn, R. S.; Cahn, W.

    2012-01-01

    Background: There is considerable variation in progressive brain volume changes in schizophrenia. Whether this is related to the clinical heterogeneity that characterizes the illness remains to be determined. This study examines the relationship between change in brain volume over time and

  20. Decreasing Irradiated Rat Lung Volume Changes Dose-Limiting Toxicity From Early to Late Effects

    Energy Technology Data Exchange (ETDEWEB)

    Veen, Sonja J. van der; Faber, Hette; Ghobadi, Ghazaleh [Department of Cell Biology, University of Groningen, University Medical Center Groningen, Groningen (Netherlands); Department of Radiation Oncology, University of Groningen, University Medical Center Groningen, Groningen (Netherlands); Brandenburg, Sytze [KVI Center for Advanced Radiation Research, University of Groningen, Groningen (Netherlands); Langendijk, Johannes A. [Department of Radiation Oncology, University of Groningen, University Medical Center Groningen, Groningen (Netherlands); Coppes, Robert P. [Department of Cell Biology, University of Groningen, University Medical Center Groningen, Groningen (Netherlands); Department of Radiation Oncology, University of Groningen, University Medical Center Groningen, Groningen (Netherlands); Luijk, Peter van, E-mail: p.van.luijk@umcg.nl [Department of Radiation Oncology, University of Groningen, University Medical Center Groningen, Groningen (Netherlands)

    2016-01-01

    Purpose: Technological developments in radiation therapy result in smaller irradiated volumes of normal tissue. Because the risk of radiation therapy-induced toxicity generally depends on irradiated volume, changing volume could change the dose-limiting toxicity of a treatment. Recently, in our rat model, we found that early radiation-induced lung dysfunction (RILD) was closely related to irradiated volume dependent vascular remodeling besides inflammation. The exact relationship between early and late RILD is still unknown. Therefore, in this preclinical study we investigated the dose-volume relationship of late RILD, assessed its dependence on early and late pathologies and studied if decreasing irradiated volume changed the dose-limiting toxicity. Methods and Materials: A volume of 25%, 32%, 50%, 63%, 88%, or 100% of the rat lung was irradiated using protons. Until 26 weeks after irradiation, respiratory rates were measured. Macrovascular remodeling, pulmonary inflammation, and fibrosis were assessed at 26 weeks after irradiation. For all endpoints dose-volume response curves were made. These results were compared to our previously published early lung effects. Results: Early vascular remodeling and inflammation correlated significantly with early RILD. Late RILD correlated with inflammation and fibrosis, but not with vascular remodeling. In contrast to the early effects, late vascular remodeling, inflammation and fibrosis showed a primarily dose but not volume dependence. Comparison of respiratory rate increases early and late after irradiation for the different dose-distributions indicated that with decreasing irradiated volumes, the dose-limiting toxicity changed from early to late RILD. Conclusions: In our rat model, different pathologies underlie early and late RILD with different dose-volume dependencies. Consequently, the dose-limiting toxicity changed from early to late dysfunction when the irradiated volume was reduced. In patients, early and late

  1. Current management of penetrating torso trauma: nontherapeutic is not good enough anymore.

    Science.gov (United States)

    Ball, Chad G

    2014-04-01

    A highly organized approach to the evaluation and treatment of penetrating torso injuries based on regional anatomy provides rapid diagnostic and therapeutic consistency. It also minimizes delays in diagnosis, missed injuries and nontherapeutic laparotomies. This review discusses an optimal sequence of structured rapid assessments that allow the clinician to rapidly proceed to gold standard therapies with a minimal risk of associated morbidity.

  2. Accuracy of conventional imaging of penetrating torso injuries in the trauma resuscitation room

    NARCIS (Netherlands)

    D.S.E. Varin (Dorien); A.N. Ringburg (Akkie); E.M.M. van Lieshout (Esther); P. Patka (Peter); I.B. Schipper (Inger)

    2009-01-01

    textabstractChest X-ray (CXR), abdominal ultrasound, cardiac ultrasound, and abdominal X-ray are the most frequently used imaging modalities to radiologically evaluate patients with penetrating torso trauma. The aim of this study was to evaluate the accuracy of these imaging modalities. From January

  3. Factors influencing liver and spleen volume changes after donor hepatectomy for living donor liver transplantation

    International Nuclear Information System (INIS)

    Bae, Ji Hee; Ryeom, Hunku; Song, Jung Hup

    2013-01-01

    To define the changes in liver and spleen volumes in the early postoperative period after partial liver donation for living-donor liver transplantation (LDLT) and to determine factors that influence liver and spleen volume changes. 27 donors who underwent partial hepatectomy for LDLT were included in this study. The rates of liver and spleen volume change, measured with CT volumetry, were correlated with several factors. The analyzed factors included the indocyanine green (ICG) retention rate at 15 minutes after ICG administration, preoperative platelet count, preoperative liver and splenic volumes, resected liver volume, resected-to-whole liver volume ratio (LV R /LV W ), resected liver volume to the sum of whole liver and spleen volume ratio [LV R /(LV W + SV 0 )], and pre and post hepatectomy portal venous pressures. In all hepatectomy donors, the volumes of the remnant liver and spleen were increased (increased rates, 59.5 ± 50.5%, 47.9 ± 22.6%). The increment rate of the remnant liver volume revealed a positive correlation with LV R /LV W (r = 0.759, p R /LV W influences the increment rate of the remnant liver volume.

  4. Automatic anatomy partitioning of the torso region on CT images by using multiple organ localizations with a group-wise calibration technique

    Science.gov (United States)

    Zhou, Xiangrong; Morita, Syoichi; Zhou, Xinxin; Chen, Huayue; Hara, Takeshi; Yokoyama, Ryujiro; Kanematsu, Masayuki; Hoshi, Hiroaki; Fujita, Hiroshi

    2015-03-01

    This paper describes an automatic approach for anatomy partitioning on three-dimensional (3D) computedtomography (CT) images that divide the human torso into several volume-of-interesting (VOI) images based on anatomical definition. The proposed approach combines several individual detections of organ-location with a groupwise organ-location calibration and correction to achieve an automatic and robust multiple-organ localization task. The essence of the proposed method is to jointly detect the 3D minimum bounding box for each type of organ shown on CT images based on intra-organ-image-textures and inter-organ-spatial-relationship in the anatomy. Machine-learning-based template matching and generalized Hough transform-based point-distribution estimation are used in the detection and calibration processes. We apply this approach to the automatic partitioning of a torso region on CT images, which are divided into 35 VOIs presenting major organ regions and tissues required by routine diagnosis in clinical medicine. A database containing 4,300 patient cases of high-resolution 3D torso CT images is used for training and performance evaluations. We confirmed that the proposed method was successful in target organ localization on more than 95% of CT cases. Only two organs (gallbladder and pancreas) showed a lower success rate: 71 and 78% respectively. In addition, we applied this approach to another database that included 287 patient cases of whole-body CT images scanned for positron emission tomography (PET) studies and used for additional performance evaluation. The experimental results showed that no significant difference between the anatomy partitioning results from those two databases except regarding the spleen. All experimental results showed that the proposed approach was efficient and useful in accomplishing localization tasks for major organs and tissues on CT images scanned using different protocols.

  5. Plasma volume changes during hypoglycaemia: the effect of arterial blood sampling

    DEFF Research Database (Denmark)

    Hilsted, J; Bendtsen, F; Christensen, N J

    1990-01-01

    To investigate whether previously reported changes in venous blood volume and composition induced by acute hypoglycaemia in humans are representative for the entire body we measured erythrocyte 51Cr content, haematocrit, plasma volume, intravascular albumin content and transcapillary escape rate...... hypoglycaemia. The magnitude of the changes in arterial and venous blood were not significantly different. These results indicate that the above changes in blood volume and composition are whole-body phenomena: furthermore, the major part of the changes are likely to occur in tissues other than upper extremity...

  6. Characterization of Target Volume Changes During Breast Radiotherapy Using Implanted Fiducial Markers and Portal Imaging

    International Nuclear Information System (INIS)

    Harris, Emma J.; Donovan, Ellen M.; Yarnold, John R.; Coles, Charlotte E.; Evans, Philip M.

    2009-01-01

    Purpose: To determine target volume changes by using volume and shape analysis for patients receiving radiotherapy after breast conservation surgery and to compare different methods of automatically identifying changes in target volume, position, size, and shape during radiotherapy for use in adaptive radiotherapy. Methods and Materials: Eleven patients undergoing whole breast radiotherapy had fiducial markers sutured into the excision cavity at the time of surgery. Patients underwent imaging using computed tomography (for planning and at the end of treatment) and during treatment by using portal imaging. A marker volume (MV) was defined by using the measured marker positions. Changes in both individual marker positions and MVs were identified manually and using six automated similarity indices. Comparison of the two types of analysis (manual and automated) was undertaken to establish whether similarity indices can be used to automatically detect changes in target volumes. Results: Manual analysis showed that 3 patients had significant MV reduction. This analysis also showed significant changes between planning computed tomography and the start of treatment for 9 patients, including single and multiple marker movement, deformation (shape change), and rotation. Four of the six similarity indices were shown to be sensitive to the observed changes. Conclusions: Significant changes in size, shape, and position occur to the fiducial marker-defined volume. Four similarity indices can be used to identify these changes, and a protocol for their use in adaptive radiotherapy is suggested

  7. Changes in superior mesenteric artery Doppler waveform during reduction of cardiac stroke volume and hypotension

    DEFF Research Database (Denmark)

    Perko, M J; Perko, Grazyna; Just, S

    1996-01-01

    the hypovolemia. Alterations in pV and pulsatility indices were closely related to changes in stroke volume, and a negative correlation was found between diastolic velocities and stroke volume. regression analysis showed no significant relation between variations in velocity parameters and blood pressure. Results...

  8. Modulation of KCNQ4 channel activity by changes in cell volume

    DEFF Research Database (Denmark)

    Hougaard, Charlotte; Klaerke, Dan A; Hoffmann, Else K

    2004-01-01

    KCNQ4 channels expressed in HEK 293 cells are sensitive to cell volume changes, being activated by swelling and inhibited by shrinkage, respectively. The KCNQ4 channels contribute significantly to the regulatory volume decrease (RVD) process following cell swelling. Under isoosmotic conditions...

  9. Changes in down dead wood volume across a chronosequence of silvicultural openings in southern Indiana forests

    Science.gov (United States)

    Michael A. Jenkins; George R. Parker

    1997-01-01

    The volume and decay stages of down dead wood were evaluated across a chronosequence of 46 silvicultural openings and 10 uncut control stands to determine how down dead wood volume changes with stand development. Openings ranged in age from 8 to 26 years and were divided into three age groups: (1) 16 years. Individual logs...

  10. Volume-change-free GeTeN films for high-performance phase-change memory

    International Nuclear Information System (INIS)

    Yin, You; Hosaka, Sumio; Zhang, Hui; Liu, Yang; Yu, Qi

    2013-01-01

    N-doping into GeTe is investigated with the aim of reducing the volume change upon crystallization, which usually induces a huge internal stress in phase-change memory devices. It is demonstrated that the thickness change upon crystallization of a N-doped GeTe (GeTeN) film is almost zero when N is doped in an appropriate amount. Cracks resulting from the stress caused by volume change disappear and the mean crystal size decreases by more than 50% upon N-doping into GeTe. It is thought that the volume-change-free behaviour is due to the formation of low-density nitride and grain refinement. (paper)

  11. Study of the seroma volume changes in the patients who underwent Accelerated Partial Breast Irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Dae Ho; Son, Sang Jun; Mun, Jun Ki; Seo, Seok Jin; Lee, Je Hee [Dept. of Radiation Oncology, Seoul National University Hospital, Seoul (Korea, Republic of)

    2016-06-15

    By analyzing seroma volume changes in the patients who underwent Partial breast radiation therapy after breast conserving surgery, we try to contribute to the improvement of radiotherapy effect. Enrolled 20 patients who underwent partial breast radiation therapy by ViewRay MRIdian System were subject. After seeking for the size of the removed sample in the patients during surgery and obtained seroma volume changes on a weekly basis. On the Basis of acquired volume, it was compared with age, term from start of the first treatment after surgery, BMI (body mass index) and the extracted sample size during surgery. And using the ViewRay MRIdian RTP System, the figure was analyzed by PTV(=seroma volume + margin) to obtain a specific volume of the Partial breast radiation therapy. The changes of seroma volume from MR simulation to the first treatment (a week) is 0~5% in 8, 5~10% in 3, 10 to 15% in 2, and 20% or more in 5 people. Two patients(A, B patient) among subjects showed the biggest change. The A patient's 100% of the prescribed dose volume is 213.08 cc, PTV is 181.93 cc, seroma volume is 15.3 cc in initial plan. However, while seroma volume decreased 65.36% to 5.3 cc, 100% of the prescribed dose volume was reduced to 3.4% to 102.43 cc and PTV also did 43.6% to 102.54 cc. In the case of the B patient, seroma volume decreased 42.57% from 20.2 cc to 11.6 cc. Because of that, 100% of the prescribed dose volume decreased 8.1% and PTV also did to 40%. As the period between the first therapy and surgery is shorter, the patient is elder and the size of sample is smaller than 100 cc, the change grow bigger. It is desirable to establish an adaptive plan according to each patient's changes of seroma volume through continuous observation. Because partial breast patients is more sensitive than WBRT patients about dose conformity in accordance with the volume change.

  12. Study of the seroma volume changes in the patients who underwent Accelerated Partial Breast Irradiation

    International Nuclear Information System (INIS)

    Kim, Dae Ho; Son, Sang Jun; Mun, Jun Ki; Seo, Seok Jin; Lee, Je Hee

    2016-01-01

    By analyzing seroma volume changes in the patients who underwent Partial breast radiation therapy after breast conserving surgery, we try to contribute to the improvement of radiotherapy effect. Enrolled 20 patients who underwent partial breast radiation therapy by ViewRay MRIdian System were subject. After seeking for the size of the removed sample in the patients during surgery and obtained seroma volume changes on a weekly basis. On the Basis of acquired volume, it was compared with age, term from start of the first treatment after surgery, BMI (body mass index) and the extracted sample size during surgery. And using the ViewRay MRIdian RTP System, the figure was analyzed by PTV(=seroma volume + margin) to obtain a specific volume of the Partial breast radiation therapy. The changes of seroma volume from MR simulation to the first treatment (a week) is 0~5% in 8, 5~10% in 3, 10 to 15% in 2, and 20% or more in 5 people. Two patients(A, B patient) among subjects showed the biggest change. The A patient's 100% of the prescribed dose volume is 213.08 cc, PTV is 181.93 cc, seroma volume is 15.3 cc in initial plan. However, while seroma volume decreased 65.36% to 5.3 cc, 100% of the prescribed dose volume was reduced to 3.4% to 102.43 cc and PTV also did 43.6% to 102.54 cc. In the case of the B patient, seroma volume decreased 42.57% from 20.2 cc to 11.6 cc. Because of that, 100% of the prescribed dose volume decreased 8.1% and PTV also did to 40%. As the period between the first therapy and surgery is shorter, the patient is elder and the size of sample is smaller than 100 cc, the change grow bigger. It is desirable to establish an adaptive plan according to each patient's changes of seroma volume through continuous observation. Because partial breast patients is more sensitive than WBRT patients about dose conformity in accordance with the volume change

  13. Functional changes in CSF volume estimated using measurement of water T2 relaxation

    NARCIS (Netherlands)

    Piechnik, S.K.; Evans, J.; Bary, L.H.; Wise, R.G.; Jezzard, P.

    2009-01-01

    Cerebrospinal fluid (CSF) provides hydraulic suspension for the brain. The general concept of bulk CSF production, circulation, and reabsorption is well established, but the mechanisms of momentary CSF volume variation corresponding to vasoreactive changes are far less understood. Nine individuals

  14. Plasma volume changes during hypoglycaemia: the effect of arterial blood sampling

    DEFF Research Database (Denmark)

    Hilsted, J; Bendtsen, Flemming; Christensen, N J

    1990-01-01

    To investigate whether previously reported changes in venous blood volume and composition induced by acute hypoglycaemia in humans are representative for the entire body we measured erythrocyte 51Cr content, haematocrit, plasma volume, intravascular albumin content and transcapillary escape rate...... hypoglycaemia. The magnitude of the changes in arterial and venous blood were not significantly different. These results indicate that the above changes in blood volume and composition are whole-body phenomena: furthermore, the major part of the changes are likely to occur in tissues other than upper extremity...... of albumin in arterial and venous blood in seven healthy subjects before and during insulin-induced hypoglycaemia. In both vascular sites blood 51Cr content and the haematocrit increased, plasma volume and intravascular albumin content decreased and the transcapillary escape rate of albumin increased during...

  15. Improved torso modelling and its influence on the localization of arhythmogenic center(s) in hearth

    Energy Technology Data Exchange (ETDEWEB)

    Jazbinsek, V; Trontelj, Z [Ljubljana Univ. (Yugoslavia). Dept. of Physics; Burghoff, M; Zimmermann, R [Physikalisch-Technische Bundesanstalt - Inst. Berlin (Germany); Oeff, M [Freie Univ. Berlin (Germany). Fachbereich Universitaetsklinikum Steglitz

    1994-11-01

    It is desirable to get noninvasively the information on the spatial position of anomalies in the cardiac conduction system. Body surface potential map and/or magnetic field distribution in the vicinity of a human chest are obtained from cardiographic measurements. With this information we start the necessary forward and inverse calculations. In this work several types of torso models (realistic torso with the NMR support, elliptic, cylinder) have been used to analyse 7 patients with Wolf-Parkinson-White syndrome. The spatial coordinates of the tip of ablation catheter, obtained by the X-ray system, have been used as a reference in the evaluation procedure of current source coordinates (the onset of the accessory pathway), calculated from the noninvasive magnetic measurements. (author). 10 refs., 2 figs., 2 tabs.

  16. Prediction of acute cardiac rejection by changes in left ventricular volumes

    International Nuclear Information System (INIS)

    Novitzky, D.; Cooper, D.K.; Boniaszczuk, J.

    1988-01-01

    Sixteen patients underwent heart transplantation (11 orthotopic, five heterotopic). Monitoring for acute rejection was by both endomyocardial biopsy (EMB) and multigated equilibrium blood pool scanning with technetium 99m-labelled red blood cells. From the scans information was obtained on left ventricular volumes (stroke, end-diastolic, and end-systolic), ejection fraction, and heart rate. Studies (208) were made in the 16 patients. There was a highly significant correlation between the reduction in stroke volume and end-diastolic volume (and a less significant correlation in end-systolic volume) and increasing acute rejection seen on EMB. Heart rate and ejection fraction did not correlate with the development of acute rejection. Correlation of a combination of changes in stroke volume and end-diastolic volume with EMB showed a sensitivity of 85% and a specificity of 96%. Radionuclide scanning is therefore a useful noninvasive tool for monitoring acute rejection

  17. Changes in cardiac output and incidence of volume overload in cirrhotics receiving 20% albumin infusion.

    Science.gov (United States)

    Shasthry, Saggere M; Kumar, Manoj; Khumuckham, Jelen S; Sarin, Shiv Kumar

    2017-08-01

    Patients with cirrhosis are prone to develop volume over load, have increased capillary permeability and latent or overt cardiomyopathy. Whether albumin infusion causes volume overload in cirrhotics has not been adequately studied. Ninety nine consecutive cirrhotic patients receiving 1gm per kg albumin infusion were evaluated for development of volume overload. Clinical, echocardiographic and haemodynamic changes were closely monitored during and after albumin infusion. Thirty (30.30%) patients developed volume overload. Patients with higher BMI (P=.003), lower CTP (P=.01) and MELD (P=.034) were more often associated with the development of volume overload. Though baseline diastolic dysfunction was present in 82.8% of the patients, it did not influence the development of volume overload or changes in the cardiac output. The cardiac output increased significantly after albumin infusion (4.9±1.554 L/min to 5.86±1.85 L/min, Palbumin infusion develop volume overload, specially, those with higher BMI and lower severity of liver disease. Cardiac output increases after albumin infusion, and, baseline diastolic dysfunction has little effect on the development of volume overload or changes in cardiac output. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  18. Dosimetric impact of prostate volume change between CT-based HDR brachytherapy fractions

    International Nuclear Information System (INIS)

    Kim, Yongbok; Hsu, I-C.; Lessard, Etienne; Vujic, Jasmina; Pouliot, Jean

    2004-01-01

    Purpose: The objective is to evaluate the prostate volume change and its dosimetric consequences after the insertion of catheters for high-dose-rate brachytherapy. Methods and Materials: For 13 consecutive patients, a spiral CT scan was acquired before each of the 2 fractions, separated on average by 20 hours. The coordinates of the catheters were obtained on 3 axial CT slices corresponding to apex, mid portion, and base portion of the prostate. A mathematical expansion model was used to evaluate the change of prostate volumes between the 2 fractions. It is based on the difference in the cube of the average distance between the centroid and catheter positions. The variation of implant dose-volume histograms between fractions was computed for plans produced by either inverse planning based on simulated annealing or geometric optimization. Results: The average magnitude of either increase or reduction in prostate volume was 7.8% (range, 2-17%). This volume change corresponds to an average prostate radius change of only 2.5% (range, 0.7-5.4%). For 5 patients, the prostate volume increased on average by 9% (range, 2-17%), whereas a reduction was observed for 8 patients by an average of 7% (range, 2-13%). More variation was observed at the prostate base than at mid or apex gland. The comparison of implant dose-volume histograms showed a small reduction of V100 receiving the prescription dose, with an average of 3.5% (range, 0.5-12%) and 2.2% (range, 1-6%) for inverse planning based on our simulated annealing and geometric optimization plans, respectively. Conclusion: Small volume change was observed between treatment fractions. This translates into small changes in dose delivered to the prostate volume

  19. The Epidemiology of Noncompressible Torso Hemorrhage in the Wars in Iraq and Afghanistan

    Science.gov (United States)

    2013-03-01

    torso vascular or pulmonary hemorrhage. Recently, Zonies and Eastridge20 reported 10 years of wartime splenic trauma man- agement with a series of 393...benchmark. J Vasc Surg. 2012;56:728Y736. 20. Zonies D, Eastridge B. Combat management of splenic injury: trends during a decade of conflict. J Trauma ...is the leading cause of potentially survivable trauma in the battlefield and has re- cently been defined using anatomic and physiologic criteria

  20. Comparative Assessment of Torso and Seat Mounted Restraint Systems using Manikins on the Vertical Deceleration Tower

    Science.gov (United States)

    2017-03-01

    AFRL-RH-WP-TR-2017-0044 Comparative Assessment of Torso and Seat Mounted Restraint Systems using Manikins on the Vertical ...Restraint Systems using Manikins on the Vertical Deceleration Tower 5a. CONTRACT NUMBER FA8650-14-D-6500-0001 5b. GRANT NUMBER 5c. PROGRAM...experimental effort involving a series of +z-axis impact tests was conducted on the 711th Human Performance Wing’s Vertical Deceleration Tower (VDT

  1. Noncompressible Torso Hemorrhage: A Review with Contemporary Definitions and Management Strategies

    Science.gov (United States)

    2012-01-01

    Criteria 1. Thoracic cavity (including lung ) 2. Solid organ injury grade 4 (liver, kidney, spleen) Hemorrhagic shocka; or need for immediate operation 3...resuscitation and warming in the intensive care unit. DCS is an extreme surgical strategy that carries a risk of infection; intra-abdominal abscess ...depending on location. Injury to the periphery Noncompressible Torso Hemorrhage 849 of the lung can be stapled off in a nonanatomic fashion using a linear

  2. Fabrication of a set of realistic torso phantoms for calibration of transuranic nuclide lung counting facilities

    International Nuclear Information System (INIS)

    Griffith, R.V.; Anderson, A.L.; Sundbeck, C.W.; Alderson, S.W.

    1983-01-01

    A set of 16 tissue equivalent torso phantoms has been fabricated for use by major laboratories involved in counting transuranic nuclides in the lung. These phantoms, which have bone equivalent plastic rib cages, duplicate the performance of the DOE Realistic Phantom set. The new phantoms (and their successors) provide the user laboratories with a highly realistic calibration tool. Moreover, use of these phantoms will allow participating laboratories to intercompare calibration information, both on formal and informal bases. 3 refs., 2 figs

  3. Responding to Social Change. Community Development Series, Volume 19.

    Science.gov (United States)

    Honikman, Basil, Ed.

    This book presents a spectrum of the environmental design and research issues of today, an introduction to the field as a whole, and an emphasis on the need for changes in attitudes and procedures in the disciplines. Contributions, multidisciplinary in approach, range from a diversity of perspectives, including urban planning, social and…

  4. Cell volume changes affect gluconeogenesis in the perfused liver of ...

    Indian Academy of Sciences (India)

    These changes were partly blocked in the presence of cycloheximide, suggesting that the aniso-osmotic regulations of gluconeogenesis possibly occurs through an inverse regulation of enzyme proteins and/or a regulatory protein synthesis in this catfish. In conclusion, gluconeogenesis appears to play a vital role in C.

  5. Analyzing temporal changes in maximum runoff volume series of the Danube River

    International Nuclear Information System (INIS)

    Halmova, Dana; Pekarova, Pavla; Onderka, Milan; Pekar, Jan

    2008-01-01

    Several hypotheses claim that more extremes in climatic and hydrologic phenomena are anticipated. In order to verify such hypotheses it is inevitable to examine the past periods by thoroughly analyzing historical data. In the present study, the annual maximum runoff volumes with t-day durations were calculated for a 130-year series of mean daily discharge of Danube River at Bratislava gauge (Slovakia). Statistical methods were used to clarify how the maximum runoff volumes of the Danube River changed over two historical periods (1876-1940 and 1941-2005). The conclusion is that the runoff volume regime during floods has not changed significantly during the last 130 years.

  6. Heteromeric Slick/Slack K+ channels show graded sensitivity to cell volume changes.

    Science.gov (United States)

    Tejada, Maria A; Hashem, Nadia; Calloe, Kirstine; Klaerke, Dan A

    2017-01-01

    Slick and Slack high-conductance K+ channels are found in the CNS, kidneys, pancreas, among other organs, where they play an important role in cell excitability as well as in ion transport processes. They are both activated by Na+ and Cl- but show a differential regulation by cell volume changes. Slick has been shown to be regulated by cell volume changes, whereas Slack is insensitive. α-subunits of these channels form homomeric as well as heteromeric channels. It is the aim of this work to explore whether the subunit composition of the Slick/Slack heteromeric channel affects the response to osmotic challenges. In order to provide with the adequate water permeability to the cell membrane of Xenopus laevis oocytes, mRNA of aquaporin 1 was co-expressed with homomeric or heteromeric Slick and Slack α-subunits. Oocytes were superfused with hypotonic or hypertonic buffers and changes in currents were measured by two-electrode voltage clamp. This work presents the first heteromeric K+ channel with a characteristic graded sensitivity to small and fast changes in cell volume. Our results show that the cell volume sensitivity of Slick/Slack heteromeric channels is dependent on the number of volume sensitive Slick α-subunits in the tetrameric channels, giving rise to graded cell volume sensitivity. Regulation of the subunit composition of a channel may constitute a novel mechanism to determine volume sensitivity of cells.

  7. Estimating neuromuscular stimulation within the human torso with Taser (registered) stimulus

    International Nuclear Information System (INIS)

    Sun Hongyu; Webster, John G

    2007-01-01

    Designers of electromuscular incapacitation devices need to know efficacy. Which areas of nerve and muscle are stimulated and are these areas adequate to cause incapacitation? This paper focuses on efficacy, which used a torso-sized finite element model with a mesh of about 5 mm. To estimate the neuromuscular regions stimulated by the Taser (registered) X26, calculations of electric current density and field strength values with 1 A inserted into the torso using the Utah 3D mesh were made. Field-times-duration values for given Taser stimulation were calculated. Then the region where the motor nerve was stimulated by the Taser was estimated by using a field-times-duration threshold from Reilly (1998 Applied Bioelectricity: From Electrical Stimulation to Electropathology (New York: Springer)). Neuromuscular stimulation occurred up to about 19 cm away from the darts and included the spinal cord. The current density at the heart for dart separation less than 10 cm was smaller than for larger dart separation. Users of finite element computer models will find information for torso models and their creation, meshing and operation

  8. Torso geometry reconstruction and body surface electrode localization using three-dimensional photography.

    Science.gov (United States)

    Perez-Alday, Erick A; Thomas, Jason A; Kabir, Muammar; Sedaghat, Golriz; Rogovoy, Nichole; van Dam, Eelco; van Dam, Peter; Woodward, William; Fuss, Cristina; Ferencik, Maros; Tereshchenko, Larisa G

    We conducted a prospective clinical study (n=14; 29% female) to assess the accuracy of a three-dimensional (3D) photography-based method of torso geometry reconstruction and body surface electrodes localization. The position of 74 body surface electrocardiographic (ECG) electrodes (diameter 5mm) was defined by two methods: 3D photography, and CT (marker diameter 2mm) or MRI (marker size 10×20mm) imaging. Bland-Altman analysis showed good agreement in X (bias -2.5 [95% limits of agreement (LoA) -19.5 to 14.3] mm), Y (bias -0.1 [95% LoA -14.1 to 13.9] mm), and Z coordinates (bias -0.8 [95% LoA -15.6 to 14.2] mm), as defined by the CT/MRI imaging, and 3D photography. The average Hausdorff distance between the two torso geometry reconstructions was 11.17±3.05mm. Thus, accurate torso geometry reconstruction using 3D photography is feasible. Body surface ECG electrodes coordinates as defined by the CT/MRI imaging, and 3D photography, are in good agreement. Copyright © 2017 Elsevier Inc. All rights reserved.

  9. Estimating neuromuscular stimulation within the human torso with Taser (registered) stimulus

    Energy Technology Data Exchange (ETDEWEB)

    Sun Hongyu [Department of Electrical and Computer Engineering, University of Wisconsin, Madison, WI 53706 (United States); Webster, John G [Department of Biomedical Engineering, University of Wisconsin, Madison, WI 53706 (United States)

    2007-11-07

    Designers of electromuscular incapacitation devices need to know efficacy. Which areas of nerve and muscle are stimulated and are these areas adequate to cause incapacitation? This paper focuses on efficacy, which used a torso-sized finite element model with a mesh of about 5 mm. To estimate the neuromuscular regions stimulated by the Taser (registered) X26, calculations of electric current density and field strength values with 1 A inserted into the torso using the Utah 3D mesh were made. Field-times-duration values for given Taser stimulation were calculated. Then the region where the motor nerve was stimulated by the Taser was estimated by using a field-times-duration threshold from Reilly (1998 Applied Bioelectricity: From Electrical Stimulation to Electropathology (New York: Springer)). Neuromuscular stimulation occurred up to about 19 cm away from the darts and included the spinal cord. The current density at the heart for dart separation less than 10 cm was smaller than for larger dart separation. Users of finite element computer models will find information for torso models and their creation, meshing and operation.

  10. Emergency Sonography Aids Diagnostic Accuracy of Torso Injuries: A Study in a Resource Limited Setting

    Directory of Open Access Journals (Sweden)

    Charles Edward Tunuka

    2014-01-01

    Full Text Available Introduction. Clinical evaluation of patients with torso trauma is often a diagnostic challenge. Extended focused assessment with sonography for trauma (EFAST is an emergency ultrasound scan that adds to the evaluation of intrathoracic abdominal and pericardial cavities done in FAST (focused assessment with sonography for trauma. Objective. This study compares EFAST (the index test with the routine standard of care (SoC investigations (the standard reference test for torso trauma injuries. Methods. A cross-sectional descriptive study was conducted over a 3-month period. Eligible patients underwent EFAST scanning and the SoC assessment. The diagnostic accuracy of EFAST was calculated using sensitivity and specificity scores. Results. We recruited 197 patients; the M : F ratio was 5 : 1, with mean age of 27 years (SD 11. The sensitivity of EFAST was 100%, the specificity was 97%, the PPV was 87%, and the NPV was 100%. It took 5 minutes on average to complete an EFAST scan. 168 (85% patients were EFAST-scanned. Most patients (82 (48% were discharged on the same day of hospitalization, while 7 (4% were still at the hospital after two weeks. The mortality rate was 18 (9%. Conclusion. EFAST is a reliable method of diagnosing torso injuries in a resource limited context.

  11. International Law and the Changing Character of War. Volume 87

    Science.gov (United States)

    2011-01-01

    the way of observable evidence. Yet the prospect of low-intensity CNA is likely to change the calculus of these decisions. With these cheap, anonymous... dental civilian deaths associated with the use of drones, the numbers (as discussed below in the sections on proportionality and military necessity) are...the use of sophisticated persis- tent surveillance, assess with much greater accuracy the anticipated effects of inci- dental loss or damage to civilian

  12. Do Acartia tonsa (Dana) eggs regulate their volume and osmolality as salinity changes?

    DEFF Research Database (Denmark)

    Hansen, Benni Winding; Drillet, Guillaume; Pedersen, Morten Foldager

    2012-01-01

    Subitaneous eggs from an euryhaline calanoid copepod Acartia tonsa were challenged by changes in salinity within the range from full strength salinity, down to zero and up to >70 psu. Egg volume changed immediately, increasing from 2.8 × 105 μm3 at full strength salinity (35 psu) to 3.8 × 105 μm3...... at 0 psu and back to its initial volume when gradually being returned to full strength salinity. Egg osmolality followed the molality of the surrounding water when challenged within a salinity range from 2 to 50 psu. Egg respiration was not affected when eggs kept at 35 psu was exposed to low salinity...... (2 psu). These results suggest that eggs are unable to regulate their volume or osmolality when challenged with changes in salinity. Gradual changes in salinity from 35 to 2 psu and back did not harm the eggs (embryos), since the hatching success remained unaffected by such changes in salinity...

  13. Change in brain and lesion volumes after CEE therapies: the WHIMS-MRI studies.

    Science.gov (United States)

    Coker, Laura H; Espeland, Mark A; Hogan, Patricia E; Resnick, Susan M; Bryan, R Nick; Robinson, Jennifer G; Goveas, Joseph S; Davatzikos, Christos; Kuller, Lewis H; Williamson, Jeff D; Bushnell, Cheryl D; Shumaker, Sally A

    2014-02-04

    To determine whether smaller brain volumes in older women who had completed Women's Health Initiative (WHI)-assigned conjugated equine estrogen-based hormone therapy (HT), reported by WHI Memory Study (WHIMS)-MRI, correspond to a continuing increased rate of atrophy an average of 6.1 to 7.7 years later in WHIMS-MRI2. A total of 1,230 WHI participants were contacted: 797 (64.8%) consented, and 729 (59%) were rescanned an average of 4.7 years after the initial MRI scan. Mean annual rates of change in total brain volume, the primary outcome, and rates of change in ischemic lesion volumes, the secondary outcome, were compared between treatment groups using mixed-effect models with adjustment for trial, clinical site, age, intracranial volumes, and time between MRI measures. Total brain volume decreased an average of 3.22 cm(3)/y in the active arm and 3.07 cm(3)/y in the placebo arm (p = 0.53). Total ischemic lesion volumes increased in both arms at a rate of 0.12 cm(3)/y (p = 0.88). Conjugated equine estrogen-based postmenopausal HT, previously assigned at WHI baseline, did not affect rates of decline in brain volumes or increases in brain lesion volumes during the 4.7 years between the initial and follow-up WHIMS-MRI studies. Smaller frontal lobe volumes were observed as persistent group differences among women assigned to active HT compared with placebo. Women with a history of cardiovascular disease treated with active HT, compared with placebo, had higher rates of accumulation in white matter lesion volume and total brain lesion volume. Further study may elucidate mechanisms that explain these findings.

  14. Longitudinal changes in total brain volume in schizophrenia: relation to symptom severity, cognition and antipsychotic medication.

    Directory of Open Access Journals (Sweden)

    Juha Veijola

    Full Text Available Studies show evidence of longitudinal brain volume decreases in schizophrenia. We studied brain volume changes and their relation to symptom severity, level of function, cognition, and antipsychotic medication in participants with schizophrenia and control participants from a general population based birth cohort sample in a relatively long follow-up period of almost a decade. All members of the Northern Finland Birth Cohort 1966 with any psychotic disorder and a random sample not having psychosis were invited for a MRI brain scan, and clinical and cognitive assessment during 1999-2001 at the age of 33-35 years. A follow-up was conducted 9 years later during 2008-2010. Brain scans at both time points were obtained from 33 participants with schizophrenia and 71 control participants. Regression models were used to examine whether brain volume changes predicted clinical and cognitive changes over time, and whether antipsychotic medication predicted brain volume changes. The mean annual whole brain volume reduction was 0.69% in schizophrenia, and 0.49% in controls (p = 0.003, adjusted for gender, educational level, alcohol use and weight gain. The brain volume reduction in schizophrenia patients was found especially in the temporal lobe and periventricular area. Symptom severity, functioning level, and decline in cognition were not associated with brain volume reduction in schizophrenia. The amount of antipsychotic medication (dose years of equivalent to 100 mg daily chlorpromazine over the follow-up period predicted brain volume loss (p = 0.003 adjusted for symptom level, alcohol use and weight gain. In this population based sample, brain volume reduction continues in schizophrenia patients after the onset of illness, and antipsychotic medications may contribute to these reductions.

  15. Serial Changes in 3-Dimensional Supraspinatus Muscle Volume After Rotator Cuff Repair.

    Science.gov (United States)

    Chung, Seok Won; Oh, Kyung-Soo; Moon, Sung Gyu; Kim, Na Ra; Lee, Ji Whan; Shim, Eungjune; Park, Sehyung; Kim, Youngjun

    2017-08-01

    There is considerable debate on the recovery of rotator cuff muscle atrophy after rotator cuff repair. To evaluate the serial changes in supraspinatus muscle volume after rotator cuff repair by using semiautomatic segmentation software and to determine the relationship with functional outcomes. Case series; Level of evidence, 4. Seventy-four patients (mean age, 62.8 ± 8.8 years) who underwent arthroscopic rotator cuff repair and obtained 3 consecutive (preoperatively, immediately postoperatively, and later postoperatively [≥1 year postoperatively]) magnetic resonance imaging (MRI) scans having complete Y-views were included. We generated a 3-dimensional (3D) reconstructed model of the supraspinatus muscle by using in-house semiautomatic segmentation software (ITK-SNAP) and calculated both the 2-dimensional (2D) cross-sectional area and 3D volume of the muscle in 3 different views (Y-view, 1 cm medial to the Y-view [Y+1 view], and 2 cm medial to the Y-view [Y+2 view]) at the 3 time points. The area and volume changes at each time point were evaluated according to repair integrity. Later postoperative volumes were compared with immediately postoperative volumes, and their relationship with various clinical factors and the effect of higher volume increases on range of motion, muscle power, and visual analog scale pain and American Shoulder and Elbow Surgeons scores were evaluated. The interrater reliabilities were excellent for all measurements. Areas and volumes increased immediately postoperatively as compared with preoperatively; however, only volumes on the Y+1 view and Y+2 view significantly increased later postoperatively as compared with immediately postoperatively ( P < .05). There were 9 patients with healing failure, and area and volume changes were significantly less later postoperatively compared with immediately postoperatively at all measurement points in these patients ( P < .05). After omitting the patients with healing failure, volume increases

  16. Evidence for the changes of pituitary volumes in patients with post-traumatic stress disorder.

    Science.gov (United States)

    Atmaca, Murad; Ozer, Omer; Korkmaz, Sevda; Taskent, Ismail; Yildirim, Hanefi

    2017-02-28

    In pubertal and postpubertal patients with post-traumatic stress disorder (PTSD), significantly greater pituitary gland volumes have been reported. Moving from this point, in the present study, we aimed to investigate pituitary gland volumes in patients with PTSD and hypothesized that volumes of the gland would be structurally changed. Volumetric magnetic resonance imaging of the pituitary gland was performed among sixteen patients with PTSD and fifteen healthy control subjects. We found that the mean volume of the pituitary gland was statistically significant and smaller than that of healthy subjects (0.69±0.08cm 3 for patient group and 0.83±0.21 for control subjects). Consequently, in the present study, we found that patients with PTSD had smaller pituitary gland volumes than those of healthy controls like other anxiety disorders. It is important to provide support for this finding in future longitudinal investigations. Copyright © 2016. Published by Elsevier B.V.

  17. Brain Volume Changes After Withdrawal of Atypical Antipsychotics in Patients With First-Episode Schizophrenia

    NARCIS (Netherlands)

    Boonstra, Geartsje; van Haren, Neeltje E. M.; Schnack, Hugo G.; Cahn, Wiepke; Burger, Huibert; Boersma, Maria; de Kroon, Bart; Grobbee, Diederick E.; Pol, Hilleke E. Hulshoff; Kahn, Rene S.

    The influence of antipsychotic medication on brain morphology in schizophrenia may confound interpretation of brain changes over time. We aimed to assess the effect of discontinuation of atypical antipsychotic medication on change in brain volume in patients. Sixteen remitted, stable patients with

  18. Changes in apparent molar water volume and DKP solubility yield insights on the Hofmeister effect.

    Science.gov (United States)

    Payumo, Alexander Y; Huijon, R Michael; Mansfield, Deauna D; Belk, Laurel M; Bui, Annie K; Knight, Anne E; Eggers, Daryl K

    2011-12-15

    This study examines the properties of a 4 × 2 matrix of aqueous cations and anions at concentrations up to 8.0 M. The apparent molar water volume, as calculated by subtracting the mass and volume of the ions from the corresponding solution density, was found to exceed the molar volume of ice in many concentrated electrolyte solutions, underscoring the nonideal behavior of these systems. The solvent properties of water were also analyzed by measuring the solubility of diketopiperazine (DKP) in 2.000 M salt solutions prepared from the same ion combinations. Solution rankings for DKP solubility were found to parallel the Hofmeister series for both cations and anions, whereas molar water volume concurred with the cation series only. The results are discussed within the framework of a desolvation energy model that attributes solute-specific changes in equilibria to solute-dependent changes in the free energy of bulk water.

  19. Changes in Apparent Molar Water Volume and DKP Solubility Yield Insights on the Hofmeister Effect

    Science.gov (United States)

    Payumo, Alexander Y.; Huijon, R. Michael; Mansfield, Deauna D.; Belk, Laurel M.; Bui, Annie K.; Knight, Anne E.; Eggers, Daryl K.

    2011-01-01

    This study examines the properties of a 4 × 2 matrix of aqueous cations and anions at concentrations up to 8.0 M. The apparent molar water volume, as calculated by subtracting the mass and volume of the ions from the corresponding solution density, was found to exceed the molar volume of ice in many concentrated electrolyte solutions, underscoring the non-ideal behavior of these systems. The solvent properties of water were also analyzed by measuring the solubility of diketopiperazine (DKP) in 2.000 M salt solutions prepared from the same ion combinations. Solution rankings for DKP solubility were found to parallel the Hofmeister series for both cations and anions, whereas molar water volume concurred with the cation series only. The results are discussed within the framework of a desolvation energy model that attributes solute-specific changes in equilibria to solute-dependent changes in the free energy of bulk water. PMID:22029390

  20. Global and regional changes of cardiopulmonary blood volume under continuous work load

    International Nuclear Information System (INIS)

    Hoeck, A.; Schuerch, P.; Freundlieb, C.; Vyska, K.; Kunz, N.; Feinendegen, L.E.; Hollmann, W.

    1980-01-01

    The present study describes a method for the continuous determination of global and regional stress-induced alterations of cardiopulmonary blood volumes in normals, trained athletes and patients with latent cardiac insufficiency. In contrast to normals and athletes there is an increase of the total cardiac blood volume in the cardiac patients. There are also significant differences in blood volume changes of the left lung between normals and athletes on the one hand and the cardiac patients on the other. The method is simple and non-hazardous; it permits the observation of the obviously different adaptation of the cardiopulmonary system during exercise in normals, athletes and cardiac patients. (orig.) [de

  1. Graded changes in enamel component volumes resulted from a short tooth bleaching procedure.

    Science.gov (United States)

    Ferreira, Artemisa Fernanda Moura; Perez, Flávia Maria de Moraes Ramos; Limeira Júnior, Francisco de Assis; de Moura, Mirella de Fátima Liberato; de Sousa, Frederico Barbosa

    2016-05-01

    To test the hypothesis that changes in enamel component volumes (mineral, organic, and water volumes, and permeability) are graded from outer to inner enamel after a short bleaching procedure. Extracted unerupted human third molars had half of their crowns bleached (single bleaching session, 3 × 15 min), and tooth shade changes in bleached parts were analyzed with a spectrophotometer. Ground sections were prepared, component volumes and permeability were quantified at histological points located at varying distances from the enamel surface (n=10 points/location), representing conditions before and after bleaching. Tooth shade changes were significant (pbleaching, except at the outer layers. Multiple analysis of covariances revealed that most of the variance of the change in enamel composition after bleaching was explained by the combination of the set of types of component volume (in decreasing order of relevance: mineral loss, organic gain, water gain, and decrease in permeability) with the set of distances from the enamel surface (graded from the enamel surface inward) (canonical R(2)=0.97; p99%). Changes in enamel composition after a short bleaching procedure followed a gradient within component volumes (mineral loss>organic gain>water gain>decrease in permeability) and decreased from the enamel surface inward. Copyright © 2016 Elsevier Ltd. All rights reserved.

  2. Mechanistic Fluid Transport Model to Estimate Gastrointestinal Fluid Volume and Its Dynamic Change Over Time.

    Science.gov (United States)

    Yu, Alex; Jackson, Trachette; Tsume, Yasuhiro; Koenigsknecht, Mark; Wysocki, Jeffrey; Marciani, Luca; Amidon, Gordon L; Frances, Ann; Baker, Jason R; Hasler, William; Wen, Bo; Pai, Amit; Sun, Duxin

    2017-11-01

    Gastrointestinal (GI) fluid volume and its dynamic change are integral to study drug disintegration, dissolution, transit, and absorption. However, key questions regarding the local volume and its absorption, secretion, and transit remain unanswered. The dynamic fluid compartment absorption and transit (DFCAT) model is proposed to estimate in vivo GI volume and GI fluid transport based on magnetic resonance imaging (MRI) quantified fluid volume. The model was validated using GI local concentration of phenol red in human GI tract, which was directly measured by human GI intubation study after oral dosing of non-absorbable phenol red. The measured local GI concentration of phenol red ranged from 0.05 to 168 μg/mL (stomach), to 563 μg/mL (duodenum), to 202 μg/mL (proximal jejunum), and to 478 μg/mL (distal jejunum). The DFCAT model characterized observed MRI fluid volume and its dynamic changes from 275 to 46.5 mL in stomach (from 0 to 30 min) with mucus layer volume of 40 mL. The volumes of the 30 small intestine compartments were characterized by a max of 14.98 mL to a min of 0.26 mL (0-120 min) and a mucus layer volume of 5 mL per compartment. Regional fluid volumes over 0 to 120 min ranged from 5.6 to 20.38 mL in the proximal small intestine, 36.4 to 44.08 mL in distal small intestine, and from 42 to 64.46 mL in total small intestine. The DFCAT model can be applied to predict drug dissolution and absorption in the human GI tract with future improvements.

  3. Climate. For a successful change. Volume 1: How to commit one's territory in an adaptation approach. Volume 2: How to implement a territorial project which integrates adaptation. Volume 3: How to understand the complexity of climate change - Scientific issues

    International Nuclear Information System (INIS)

    2013-12-01

    The first volume presents the climate issue as a world issue as well as a local issue (historic context of adaptation to climate change effects, legal obligation for local communities, indicators of direct and indirect effects of climate change, economic impacts), and presents adaptation as a way of action at a local level (definition of a strategy, articulation between works on greenhouse gas emissions and those on adaptation, actions to be implemented, action follow-up and adjustment). The second volume describes how to communicate and talk about climate change, and more specifically about the above-mentioned issues (reality of climate change, indirect and direct effects, obligations and responsibilities for local communities, economic impacts). It addresses the issue of climate change in the Rhone-Alpes region: adaptation within the regional scheme on climate, air and energy (SRCAE), role of local communities. It presents an action methodology: to inform and organise, to prepare the mobilisation of actors, to prepare the territory vulnerability diagnosis, to define the adaptation strategy, and to implement, follow-up and assess the action. The third volume proposes a set of sheets containing scientific information and data related to climate change: factors of climate variability, current global warming, greenhouse gases and aerosols, physical-chemical principles involved in greenhouse effect, carbon sinks and carbon sources, effects of land assignment and agriculture, combined effects of mankind actions on the atmosphere, climate change and oceans, climate change and cryo-sphere, climate change and biodiversity, extreme meteorological and climate events and their consequences

  4. Brain putamen volume changes in newly-diagnosed patients with obstructive sleep apnea

    Directory of Open Access Journals (Sweden)

    Rajesh Kumar

    2014-01-01

    Full Text Available Obstructive sleep apnea (OSA is accompanied by cognitive, motor, autonomic, learning, and affective abnormalities. The putamen serves several of these functions, especially motor and autonomic behaviors, but whether global and specific sub-regions of that structure are damaged is unclear. We assessed global and regional putamen volumes in 43 recently-diagnosed, treatment-naïve OSA (age, 46.4 ± 8.8 years; 31 male and 61 control subjects (47.6 ± 8.8 years; 39 male using high-resolution T1-weighted images collected with a 3.0-Tesla MRI scanner. Global putamen volumes were calculated, and group differences evaluated with independent samples t-tests, as well as with analysis of covariance (covariates; age, gender, and total intracranial volume. Regional differences between groups were visualized with 3D surface morphometry-based group ratio maps. OSA subjects showed significantly higher global putamen volumes, relative to controls. Regional analyses showed putamen areas with increased and decreased tissue volumes in OSA relative to control subjects, including increases in caudal, mid-dorsal, mid-ventral portions, and ventral regions, while areas with decreased volumes appeared in rostral, mid-dorsal, medial-caudal, and mid-ventral sites. Global putamen volumes were significantly higher in the OSA subjects, but local sites showed both higher and lower volumes. The appearance of localized volume alterations points to differential hypoxic or perfusion action on glia and other tissues within the structure, and may reflect a stage in progression of injury in these newly-diagnosed patients toward the overall volume loss found in patients with chronic OSA. The regional changes may underlie some of the specific deficits in motor, autonomic, and neuropsychologic functions in OSA.

  5. Comparison of doses according to change of bladder volume in treatment of prostate cancer

    Energy Technology Data Exchange (ETDEWEB)

    Kwon, Kyung Tae [Dept. of Radiologic Technology, Dongnam Health University, Suwon (Korea, Republic of); Min, Jung Whan [Dept. of Radiological Technology, Shingu University, Seongnam (Korea, Republic of)

    2017-09-15

    In the case of radiation therapy for prostate cancer, a balloon infused with a certain amount of air through the anus is used to reduce rectal dose. Because of the reason, radiation therapy for prostate cancer has acquired CBCT for daily image induction. In order to maintain the anatomical structure most similar to the first CT taken before treatment, it is pretreated, but it can not be said to be perfectly consistent. In two actual treatment regimens, the volume of the bladder was measured as 45.82 cc and 63.43 cc, and the equivalent diameter was 4.4 cm and 4.9 cm. As a result of this study, the mean volume of the bladder was estimated to be 56.2 cc, 105.6 cc by 20 CBCT. The mean dose of CBCT was 1.74% and the mean Bladder mean dose was 96.67%. In case B, PTV mean dose was 4.31%, Bladder mean Dose was estimated to be 97.35%. The changes in the volume of the bladder resulted in changes in the dose of PTV and bladder. The correlation coefficient of bladder dose according to the change of bladder volume showed linearity of mean dose R2= -0.94. The correlation coefficient of the PTV dose according to the volume change of the bladder showed linearity of mean dose R2= 0.04. It was found that the dose change of PTV was larger than that of bladder according to the change of bladder volume.

  6. Patient-specific model of a scoliotic torso for surgical planning

    Science.gov (United States)

    Harmouche, Rola; Cheriet, Farida; Labelle, Hubert; Dansereau, Jean

    2013-03-01

    A method for the construction of a patient-specific model of a scoliotic torso for surgical planning via inter-patient registration is presented. Magnetic Resonance Images (MRI) of a generic model are registered to surface topography (TP) and X-ray data of a test patient. A partial model is first obtained via thin-plate spline registration between TP and X-ray data of the test patient. The MRIs from the generic model are then fit into the test patient using articulated model registration between the vertebrae of the generic model's MRIs in prone position and the test patient's X-rays in standing position. A non-rigid deformation of the soft tissues is performed using a modified thin-plate spline constrained to maintain bone rigidity and to fit in the space between the vertebrae and the surface of the torso. Results show average Dice values of 0:975 +/- 0:012 between the MRIs following inter-patient registration and the surface topography of the test patient, which is comparable to the average value of 0:976 +/- 0:009 previously obtained following intra-patient registration. The results also show a significant improvement compared to rigid inter-patient registration. Future work includes validating the method on a larger cohort of patients and incorporating soft tissue stiffness constraints. The method developed can be used to obtain a geometric model of a patient including bone structures, soft tissues and the surface of the torso which can be incorporated in a surgical simulator in order to better predict the outcome of scoliosis surgery, even if MRI data cannot be acquired for the patient.

  7. How a change in the interaction potential affects the p-wave scattering volume

    International Nuclear Information System (INIS)

    Jamieson, M J; Dalgarno, A

    2012-01-01

    We derive a simple expression for the change in the s-wave scattering length in terms of zero-energy wavefunctions, we generalize it to obtain an expression for the change in the p-wave scattering volume and we use both expressions to derive the first order differential equations of variable phase theory that are satisfied by the closely related accumulated scattering length and volume. We provide numerical demonstrations for the example of a pair of hydrogen atoms interacting via the X 1 Σ + g molecular state. (fast track communication)

  8. Changes in forced expiratory volume in 1 second over time in COPD

    DEFF Research Database (Denmark)

    Vestbo, Jørgen; Edwards, Lisa D; Scanlon, Paul D

    2011-01-01

    A key feature of chronic obstructive pulmonary disease (COPD) is an accelerated rate of decline in forced expiratory volume in 1 second (FEV(1)), but data on the variability and determinants of this change in patients who have established disease are scarce.......A key feature of chronic obstructive pulmonary disease (COPD) is an accelerated rate of decline in forced expiratory volume in 1 second (FEV(1)), but data on the variability and determinants of this change in patients who have established disease are scarce....

  9. Regional brain volumes, diffusivity, and metabolite changes after electroconvulsive therapy for severe depression

    DEFF Research Database (Denmark)

    Jørgensen, A.; Magnusson, P.; Hanson, Lars G.

    2016-01-01

    , and metabolite changes in 19 patients receiving ECT for severe depression. Other regions of interest included the amygdala, dorsolateral prefrontal cortex (DLPFC), orbitofrontal cortex, and hypothalamus. Patients received a 3T MR scan before ECT (TP1), 1 week (TP2), and 4 weeks (TP3) after ECT. Results......: Hippocampal and amygdala volume increased significantly at TP2 and continued to be increased at TP3. DLPFC exhibited a transient volume reduction at TP2. DTI revealed a reduced anisotropy and diffusivity of the hippocampus at TP2. We found no significant post-ECT changes in brain metabolite concentrations...

  10. Change in volume of lumpectomy cavity during external-beam irradiation of the intact breast

    International Nuclear Information System (INIS)

    Jacobson, Geraldine; Betts, Vicki; Smith, Brian

    2006-01-01

    Purpose: Definition of the lumpectomy cavity is an important component of irradiation of the breast. We use computed tomography (CT)-based planning and contour the lumpectomy volume on the planning CT. We obtained a second CT in the 4th or 5th week of treatment for boost planning and compared the volume change with the first planning-CT scan. Methods and Materials: This retrospective study reviewed the planning-CT data for 20 patients. In the first CT, images were obtained from the mandible to 2 cm below the breast in 3-mm slices. In the second CT, for the boost, images were obtained from the top to the bottom of the clinically defined breast, in 3-mm slices. Lumpectomy cavities were contoured on both CT scans and volumes compared. Results: Sixteen of the 20 patients (80%) had more than a 20% decrease from the first to the second volume, with a corresponding 95% confidence interval. The mean decrease was 16.13 cc, with a standard deviation of 14.05. The Spearman correlation coefficient of 0.18 did not show a significant correlation between the initial volume and the percent change. Conclusions: During external breast irradiation, many patients will have significant volume reduction in the lumpectomy cavity. Because CT-based definition of the lumpectomy cavity can influence the planning of a boost technique, further study appears warranted

  11. Involvement of upper torso stress amplification, tissue compression and distortion in the pathogenesis of keloids.

    Science.gov (United States)

    Bux, Shamin; Madaree, Anil

    2012-03-01

    Keloids are benign tumours composed of fibrous tissue produced during excessive tissue repair triggered by minor injury, trauma or surgical incision. Although it is recognized that keloids have a propensity to form in the upper torso of the body, the predisposing factors responsible for this have not been investigated. It is crucial that the aetiopathoical factors implicated in keloid formation be established to provide guidelines for well-informed more successful treatment. We compared keloid-prone and keloid-protected skin, identified pertinent morphological differences and explored how inherent structural characteristics and intrinsic factors may promote keloid formation. It was determined that keloid prone areas were covered with high tension skin that had low stretch and a low elastic modulus when compared with skin in keloid protected areas where the skin was lax with a high elastic modulus and low pre-stress level. Factors contributing to elevated internal stress in keloid susceptible skin were the protrusion of hard connective tissue such as bony prominences or cartilage into the dermis of skin as well as inherent skin characteristics such as the bundled arrangement of collagen in the reticular dermis, the existent high tension, the low elastic modulus, low stretch ability, contractile forces exerted by wound healing fibroblastic cells and external forces. Stress promotes keloid formation by causing dermal distortion and compression which subsequently stimulate proliferation and enhanced protein synthesis in wound healing fibroblastic cells. The strain caused by stress also compresses and occludes microvessels causing ischaemic effects and reperfusion injury which stimulate growth when blood rich in growth factors returns to the tissue. The growth promoting effects of increased internal stress, primarily, and growth factors released by reperfusing blood, manifest in keloid formation. Other inherent skin characteristics promoting keloid growth during the

  12. EFFECT OF SITTING POSTURE ON THORACIC CONFIGURATION AND CHANGES IN VOLUME OF HEMITHORACES

    Directory of Open Access Journals (Sweden)

    Shōbo A

    2017-06-01

    Full Text Available Background: Poor posture is detrimental to breathing. Our purpose was to investigate the effect of upright and hunchbacked sitting on thoracic configuration and changes in the volume of the thorax during quiet and volitional deep breathing. Methods: The participants were 11 healthy men with a mean age of 21.6 years, mean body mass of 59.8 kg, mean height of 169.7 cm and a body mass index of 20.7 kg/m2. Eighty-four reflective markers were placed on the trunk. Three-dimensional motion analysis measured the volume within the hemithoraces. To calculate upper and lower thoracic volumes, six imaginary hexahedra were visualized using four reflective markers for each on both aspects of the thorax. Each hexahedron was divided into three imaginary triangular pyramids to calculate positional vectors. Finally, the volume for the hexahedra and triangular pyramids was calculated. Upper thoracic volume encompassed a space from the sternal notch to a midpoint on the ventral aspect of the third rib and the lower thoracic volume from the xiphoid process to the midpoint on tenth rib’s dorsal aspect. Results: In hunchbacked sitting during quiet breathing the left lower hemithorax yielded a significantly larger volume (p=0.003, and both breathing patterns during inspiration and expiration yielded a significantly greater change in thoracic configuration (p=0.01, p=0.016. Conclusion: Findings suggested that, in a hunchbacked sitting, there was decreased thoracic asymmetry with re-establishment of thoracic vertebral alignment, consequently stabilizing the sitting position, but breathing was suppressed and tidal volume decreased. Physiotherapy should aim at ensuring correction of hunchbacked posture and maintenance of thoracic symmetry.

  13. Susceptibility contrast imaging of CO2-induced changes in the blood volume of the human brain

    DEFF Research Database (Denmark)

    Rostrup, Egill; Larsson, H B; Toft, P B

    1996-01-01

    PURPOSE: To investigate changes in the regional cerebral blood volume (rCBV) in human subjects during rest and hypercapnia by MR imaging, and to compare the results from contrast-enhanced and noncontrast-enhanced susceptibility-weighted imaging. MATERIAL AND METHODS: Five healthy volunteers (aged...

  14. Changes in lung volume and ventilation during surfactant treatment in ventilated preterm infants

    NARCIS (Netherlands)

    Miedema, Martijn; de Jongh, Frans H.; Frerichs, Inez; van Veenendaal, Mariëtte B.; van Kaam, Anton H.

    2011-01-01

    The immediate and regional effects of exogenous surfactant in open lung high-frequency oscillatory ventilated (HFOV) preterm infants are unknown. To assess regional changes in lung volume, mechanics, and ventilation during and after surfactant administration in HFOV preterm infants with respiratory

  15. Changes in forced expiratory volume in 1 second over time in COPD

    DEFF Research Database (Denmark)

    Vestbo, Jørgen; Edwards, Lisa D; Scanlon, Paul D

    2011-01-01

    A key feature of chronic obstructive pulmonary disease (COPD) is an accelerated rate of decline in forced expiratory volume in 1 second (FEV(1)), but data on the variability and determinants of this change in patients who have established disease are scarce....

  16. Challenges in Accommodating Volume Change of Si Anodes for Li-Ion Batteries.

    Science.gov (United States)

    Ko, Minseong; Chae, Sujong; Cho, Jaephil

    2015-11-01

    Si has been considered as a promising alternative anode for next-generation Li-ion batteries (LIBs) because of its high theoretical energy density, relatively low working potential, and abundance in nature. However, Si anodes exhibit rapid capacity decay and an increase in the internal resistance, which are caused by the large volume changes upon Li insertion and extraction. This unfortunately limits their practical applications. Therefore, managing the total volume change remains a critical challenge for effectively alleviating the mechanical fractures and instability of solid-electrolyte-interphase products. In this regard, we review the recent progress in volume-change-accommodating Si electrodes and investigate their ingenious structures with significant improvements in the battery performance, including size-controlled materials, patterned thin films, porous structures, shape-preserving shell designs, and graphene composites. These representative approaches potentially overcome the large morphologic changes in the volume of Si anodes by securing the strain relaxation and structural integrity in the entire electrode. Finally, we propose perspectives and future challenges to realize the practical application of Si anodes in LIB systems.

  17. Surprising volume change in PPy(DBS): An atomic force microscopy study

    DEFF Research Database (Denmark)

    Smela, E.; Gadegaard, N.

    1999-01-01

    Communication: Conjugated polymers such as polypyrrole (PPy) have potential use as artificial muscles or in microsystems such as valves for micro-fluid handling. One of the most important parameters in such uses is the magnitude of volume change during associated redox processes; however, until now...... estimates have varied greatly. Atomic force microscopy is reported here as allowing direct measurement of the in situ thickness change during oxidation and reduction of thin films of PPy doped with dodecylbenzenesulfonate....

  18. Tissue-equivalent torso phantom for calibration of transuranic-nuclide counting facilities

    International Nuclear Information System (INIS)

    Griffith, R.V.; Anderson, A.L.; Dean, P.N.; Fisher, J.C.; Sundbeck, C.W.

    1986-01-01

    Several tissue-equivalent human-torso phantoms have been constructed for the calibration of counting systems used for in-vivo measurement of transuranic radionuclides. The phantoms contain a simulated human rib cage (in some cases, real bone) and removable model organs, and they include tissue-equivalent chest plates that can be placed over the torso to simulate people with a wide range of statures. The organs included are the lungs, liver, and tracheobronchial lymph nodes. Polyurethane with varying concentrations of added calcium was used to simulate the linear photon-attenuation properties of various human tissues, including lean muscle, adipose-muscle mixtures, cartilage, and bone. Foamed polyurethane was used to simulate lung tissue. Organs have been loaded with highly pure 238 Pu, 239 Pu, 241 Am, and other radionuclides of interest. The validity of the phantom as a calibration standard has been checked in separate intercomparison studies using human subjects whose lungs contained a plutonium simulant. The resulting phantom calibration factors generally compared to within +-20% of the average calibration factors obtained for the human subjects

  19. Coordinated three-dimensional motion of the head and torso by dynamic neural networks.

    Science.gov (United States)

    Kim, J; Hemami, H

    1998-01-01

    The problem of trajectory tracking control of a three dimensional (3D) model of the human upper torso and head is considered. The torso and the head are modeled as two rigid bodies connected at one point, and the Newton-Euler method is used to derive the nonlinear differential equations that govern the motion of the system. The two-link system is driven by six pairs of muscle like actuators that possess physiologically inspired alpha like and gamma like inputs, and spindle like and Golgi tendon organ like outputs. These outputs are utilized as reflex feedback for stability and stiffness control, in a long loop feedback for the purpose of estimating the state of the system (somesthesis), and as part of the input to the controller. Ideal delays of different duration are included in the feedforward and feedback paths of the system to emulate such delays encountered in physiological systems. Dynamical neural networks are trained to learn effective control of the desired maneuvers of the system. The feasibility of the controller is demonstrated by computer simulation of the successful execution of the desired maneuvers. This work demonstrates the capabilities of neural circuits in controlling highly nonlinear systems with multidelays in their feedforward and feedback paths. The ultimate long range goal of this research is toward understanding the working of the central nervous system in controlling movement. It is an interdisciplinary effort relying on mechanics, biomechanics, neuroscience, system theory, physiology and anatomy, and its short range relevance to rehabilitation must be noted.

  20. Intrathecal volume changes in lumbar spinal canal stenosis following extension and flexion: An experimental cadaver study.

    Science.gov (United States)

    Teske, Wolfram; Schwert, Martin; Zirke, Sonja; von Schulze Pellengahr, Christoph; Wiese, Matthias; Lahner, Matthias

    2015-01-01

    The spinal canal stenosis is a common disease in elderly. The thecal sac narrowing is considered as the anatomical cause for the disease. There is evidence that the anatomical proportions of the lumbar spinal canal are influenced by postural changes. The liquor volume shift during these postural changes is a valuable parameter to estimate the dynamic qualities of this disease. The aim of this human cadaver study was the determination of intrathecal fluid volume changes during the lumbar flexion and the extension. A special measuring device was designed and built for the study to investigate this issue under controlled conditions. The measuring apparatus fixed the lumbar spine firmly and allowed only flexion and extension. The dural sac was closed water tight. The in vitro changes of the intrathecal volumes during the motion cycle were determined according to the principle of communicating vessels. Thirteen human cadaver spines from the Institute of Anatomy were examined in a test setting with a continuous adjustment of motion. The diagnosis of the lumbar spinal stenosis was confirmed by a positive computer tomography prior testing. The volume changes during flexion and extension cycles were measured stepwise in a 2 degree distance between 18° flexion and 18° extension. Three complete series of measurements were performed for each cadaver. Two specimens were excluded because of fluid leaks from further investigation. The flexion of the lumbar spine resulted in an intrathecal volume increase. The maximum volume effects were seen in the early flexion positions of 2° and 4°. The spine reclination resulted in a volume reduction. The maximum extension effect was seen between 14° and 16°. According to our results, remarkable volume effects were seen in the early movements of the lumbar spine especially for the flexion. The results support the concept of the spinal stenosis as a dynamic disease and allow a better understanding of the pathophysiology of this

  1. Positron Annihilation as a Probe of Free Volume Changes in Polyoxymethylene-copolymer

    International Nuclear Information System (INIS)

    Mohamed, H.F.M.; Abdel-Hady, E.E.; Farid, S.S.

    2005-01-01

    The positron annihilation lifetime measurements have been carried out to study the free volume properties of polyoxymethylene-copolymer (POM). The effect of temperature changes on free volume hole sizes and hole size distribution has been investigated over the temperature range (5-100 degree C). All PAL spectra were analyzed with LT program, which is a finite term lifetime analysis and by MELT which is a continuous lifetime analysis. The free volume sites probed by o-Ps increase in size with increasing temperature. PALS measurements revealed the glass transition temperature (Tg) at 15 degree C. Below the glass transition temperature the hole size slowly (linearly) increases with temperatures, while the slope is steeper above Tg. The temperature of this transition as measured by PALS has turned out to be somewhat lower than what is obtained with differential scanning calorimetry (DSC). At room temperature the results show a narrow distribution, reflecting that the free volume holes are small and of rather equal size. As the temperature is raised, the distribution broadens. The largest change in distribution width will be discussed on the frame of the free volume model

  2. Relationship of carotid arterial functional and structural changes to left atrial volume in untreated hypertension.

    Science.gov (United States)

    Jaroch, Joanna; Rzyczkowska, Barbara; Bociąga, Zbigniew; Vriz, Olga; Driussi, Caterina; Loboz-Rudnicka, Maria; Dudek, Krzysztof; Łoboz-Grudzień, Krystyna

    2016-04-01

    The contribution of arterial functional and structural changes to left ventricular (LV) diastolic dysfunction has been the area of recent research. There are some studies on the relationship between arterial stiffness (a.s.) and left atrial (LA) remodelling as a marker of diastolic burden. Little is known about the association of arterial structural changes and LA remodelling in hypertension (H). The aim of this study was to examine the relationship between carotid a.s. and intima-media thickness (IMT) and LA volume in subjects with H. The study included 245 previously untreated hypertensives (166 women and 79 men, mean age 53.7 ± 11.8 years). Each patient was subjected to echocardiography with measurement of LA volume, evaluation of left ventricular hypertrophy (LVH) and LV systolic/diastolic function indices, integrated assessment of carotid IMT and echo-tracking of a.s. and wave reflection parameters. Univariate regression analysis revealed significant correlations between indexed LA volume and selected clinical characteristics, echocardiographic indices of LVH and LV diastolic/systolic function and a.s./wave reflection parameters. The following parameters were identified as independent determinants of indexed LA volume on multivariate regression analysis: diastolic blood pressure (beta = -0.229, P arterial stiffness but not intima-media thickness and LA volume in patients with untreated hypertension.

  3. Changes in extracellular muscle volume affect heart rate and blood pressure responses to static exercise

    Science.gov (United States)

    Baum, K.; Essfeld, D.; Stegemann, J.

    To investigate the effect of μg-induced peripheral extracellular fluid reductions on heart rate and blood pressure during isometric exercise, six healthy male subjects performed three calf ergometer test with different extracellular volumes of working muscles. In all tests, body positions during exercise were identical (supine with the knee joint flexed to 900). After a pre-exercise period of 25 min, during which calf volumes were manipulated, subjects had to counteract an external force of 180 N for 5 min. During the pre-exercise period three different protocols were applied. Test A: Subjects rested in the exercise position; test B: Body position was the same as in A but calf volume was increased by venous congestion (cuffs inflated to 80 mm Hg); test C: Calf volumes were decreased by a negative hydrostatic pressure (calves about 40 cm above heart level with the subjects supine). To clamp the changed calf volumes in tests B and C, cuffs were inflated to 300 mm Hg 5 min before the onset of exercise. This occlusion was maintained until termination of exercise. Compared to tests A and B, the reduced volume of test C led to significant increases in heart rate and blood pressure during exercise. Oxygen uptake did not exceed resting levels in B and C until cuffs were deflated, indicating that exclusively calf muscles contributed to the neurogenic peripheral drive. It is concluded that changes in extracellular muscle volume have to be taken into account when comparing heart rate and blood pressure during lg- and μg- exercise.

  4. Acute changes in forearm venous volume and tone using radionuclide plethysmography

    International Nuclear Information System (INIS)

    Manyari, D.E.; Malkinson, T.J.; Robinson, V.; Smith, E.R.; Cooper, K.E.

    1988-01-01

    In this investigation blood pool scintigraphy was validated as a method to study acute changes in human forearm veins. Changes in regional forearm vascular volume (capacity) and the occluding pressure-volume (P-V) relationship induced by sublingual nifedipine (NIF) and nitroglycerin (GTN) were recorded in 16 patients with simultaneous data collection by the radionuclide and the mercury-in-rubber strain-gauge techniques. The standard error of estimate (Syx) between successive control measurements using the radionuclide method was 3.1% compared with 3.2% for the strain-gauge method. The venous P-V curves were highly reproducible using both techniques. Strain gauge and radionuclide measurements of acute changes in forearm venous volume correlated well (r = 0.86; Syx = 7%, n = 156). After 20 mg of NIF or 0.6 mg of GTN, mean heart rate increased from 71 +/- 10 to 77 +/- 9 and from 68 +/- 10 to 75 +/- 11 beats/min, respectively, and group systolic blood pressure decreased from 128 +/- 22 to 120 +/- 19 and from 136 +/- 18 to 126 +/- 23 mmHg, respectively (P less than 0.05). At venous occluding pressures of 0 and 30 mmHg, the forearm vascular volume did not change after NIF (2 +/- 4 and -1 +/- 4%; P greater than 0.05), whereas it increased after GTN (8 +/- 5 and 12 +/- 7%; P less than 0.001). The forearm venous P-V relationship did not change after NIF, whereas a significant rightward shift (venodilation, with an increase in unstressed volume) occurred after GTN

  5. Whole Prostate Volume and Shape Changes with the Use of an Inflatable and Flexible Endorectal Coil

    International Nuclear Information System (INIS)

    Osman, M.; Shebel, H.; Sankineni, S.; Bernardo, M.L.; Daar, D.; Choyke, P.L.; Turkbey, B.; Agarwal, H.K.; Osman, M.; Shebel, H.; Bernardo, M.L.; Wood, P.J.; Pinto, P.A.; Agarwal, H.K.

    2014-01-01

    To determine to what extent an inflatable endorectal coil (ERC) affects whole prostate (WP) volume and shape during prostate MRI. Materials and Methods. 79 consecutive patients underwent T2W MRI at 3T first with a 6-channel surface coil and then with the combination of a 16-channel surface coil and ERC in the same imaging session. WP volume was assessed by manually contouring the prostate in each T2W axial slice. PSA density was also calculated. The maximum anterior-posterior (AP), left-right (LR), and cranio caudal (CC) prostate dimensions were measured. Changes in WP prostate volume, PSA density, and prostate dimensions were then evaluated. Results. In 79 patients, use of an ERC yielded no significant change in whole prostate volume (0.6 ± 5.7 %, Ρ=0.270) and PSA density (-0.2 ±5.6%,Ρ=0.768 ). However, use of an ERC significantly decreased the AP dimension of the prostate by -8.6 ±7.8%(Ρ<0.001), increased LR dimension by 4.5 ± 5.8 %(Ρ<0.001), and increased the CC dimension by 8.8 ±6.9 %( Ρ<0.001). Conclusion. Use of an ERC in prostate MRI results in the shape deformation of the prostate gland with no significant change in the volume of the prostate measured on T2W MRI. Therefore, WP volumes calculated on ERC MRI can be reliably used in clinical work flow.

  6. A lattice Boltzmann coupled to finite volumes method for solving phase change problems

    Directory of Open Access Journals (Sweden)

    El Ganaoui Mohammed

    2009-01-01

    Full Text Available A numerical scheme coupling lattice Boltzmann and finite volumes approaches has been developed and qualified for test cases of phase change problems. In this work, the coupled partial differential equations of momentum conservation equations are solved with a non uniform lattice Boltzmann method. The energy equation is discretized by using a finite volume method. Simulations show the ability of this developed hybrid method to model the effects of convection, and to predict transfers. Benchmarking is operated both for conductive and convective situation dominating solid/liquid transition. Comparisons are achieved with respect to available analytical solutions and experimental results.

  7. Tracking Regional Tissue Volume and Function Change in Lung Using Image Registration

    Directory of Open Access Journals (Sweden)

    Kunlin Cao

    2012-01-01

    Full Text Available We have previously demonstrated the 24-hour redistribution and reabsorption of bronchoalveolar lavage (BAL fluid delivered to the lung during a bronchoscopic procedure in normal volunteers. In this work we utilize image-matching procedures to correlate fluid redistribution and reabsorption to changes in regional lung function. Lung CT datasets from six human subjects were used in this study. Each subject was scanned at four time points before and after BAL procedure. Image registration was performed to align images at different time points and different inflation levels. The resulting dense displacement fields were utilized to track tissue volume changes and reveal deformation patterns of local parenchymal tissue quantitatively. The registration accuracy was assessed by measuring landmark matching errors, which were on the order of 1 mm. The results show that quantitative-assessed fluid volume agreed well with bronchoscopist-reported unretrieved BAL volume in the whole lungs (squared linear correlation coefficient was 0.81. The average difference of lung tissue volume at baseline and after 24 hours was around 2%, which indicates that BAL fluid in the lungs was almost absorbed after 24 hours. Regional lung-function changes correlated with the presence of BAL fluid, and regional function returned to baseline as the fluid was reabsorbed.

  8. Heteromeric Slick/Slack K+ channels show graded sensitivity to cell volume changes

    DEFF Research Database (Denmark)

    Tejada, Maria A; Hashem, Nadia; Callø, Kirstine

    2017-01-01

    Slick and Slack high-conductance K+ channels are found in the CNS, kidneys, pancreas, among other organs, where they play an important role in cell excitability as well as in ion transport processes. They are both activated by Na+ and Cl- but show a differential regulation by cell volume changes....... Slick has been shown to be regulated by cell volume changes, whereas Slack is insensitive. α-subunits of these channels form homomeric as well as heteromeric channels. It is the aim of this work to explore whether the subunit composition of the Slick/Slack heteromeric channel affects the response...... to osmotic challenges. In order to provide with the adequate water permeability to the cell membrane of Xenopus laevis oocytes, mRNA of aquaporin 1 was co-expressed with homomeric or heteromeric Slick and Slack α-subunits. Oocytes were superfused with hypotonic or hypertonic buffers and changes in currents...

  9. 3D mapping of cerebrospinal fluid local volume changes in patients with hydrocephalus treated by surgery: preliminary study

    International Nuclear Information System (INIS)

    Hodel, Jerome; Besson, Pierre; Pruvo, Jean-Pierre; Leclerc, Xavier; Rahmouni, Alain; Grandjacques, Benedicte; Luciani, Alain; Petit, Eric; Lebret, Alain; Outteryck, Olivier; Benadjaoud, Mohamed Amine; Maraval, Anne; Decq, Philippe

    2014-01-01

    To develop automated deformation modelling for the assessment of cerebrospinal fluid (CSF) local volume changes in patients with hydrocephalus treated by surgery. Ventricular and subarachnoid CSF volume changes were mapped by calculating the Jacobian determinant of the deformation fields obtained after non-linear registration of pre- and postoperative images. A total of 31 consecutive patients, 15 with communicating hydrocephalus (CH) and 16 with non-communicating hydrocephalus (NCH), were investigated before and after surgery using a 3D SPACE (sampling perfection with application optimised contrast using different flip-angle evolution) sequence. Two readers assessed CSF volume changes using 3D colour-encoded maps. The Evans index and postoperative volume changes of the lateral ventricles and sylvian fissures were quantified and statistically compared. Before surgery, sylvian fissure and brain ventricle volume differed significantly between CH and NCH (P = 0.001 and P = 0.025, respectively). After surgery, 3D colour-encoded maps allowed for the visual recognition of the CSF volume changes in all patients. The amounts of ventricle volume loss of CH and NCH patients were not significantly different (P = 0.30), whereas readjustment of the sylvian fissure volume was conflicting in CH and NCH patients (P < 0.001). The Evans index correlated with ventricle volume in NCH patients. 3D mapping of CSF volume changes is feasible providing a quantitative follow-up of patients with hydrocephalus. (orig.)

  10. 3D mapping of cerebrospinal fluid local volume changes in patients with hydrocephalus treated by surgery: preliminary study

    Energy Technology Data Exchange (ETDEWEB)

    Hodel, Jerome [Hopital Roger Salengro, Department of Neuroradiology, Lille (France); Hopital Roger Salengro, Service de Neuroradiologie, Lille (France); Besson, Pierre; Pruvo, Jean-Pierre; Leclerc, Xavier [Hopital Roger Salengro, Department of Neuroradiology, Lille (France); Rahmouni, Alain; Grandjacques, Benedicte; Luciani, Alain [Hopital Henri Mondor, Department of Radiology, Creteil (France); Petit, Eric; Lebret, Alain [Signals Images and Intelligent Systems Laboratory, Creteil (France); Outteryck, Olivier [Hopital Roger Salengro, Department of Neurology, Lille (France); Benadjaoud, Mohamed Amine [Radiation Epidemiology Team, CESP, Centre for Research in Epidemiology and Population Health U1018, Villejuif (France); Maraval, Anne [Hopital Henri Mondor, Department of Neuroradiology, Creteil (France); Decq, Philippe [Hopital Henri Mondor, Department of Neurosurgery, Creteil (France)

    2014-01-15

    To develop automated deformation modelling for the assessment of cerebrospinal fluid (CSF) local volume changes in patients with hydrocephalus treated by surgery. Ventricular and subarachnoid CSF volume changes were mapped by calculating the Jacobian determinant of the deformation fields obtained after non-linear registration of pre- and postoperative images. A total of 31 consecutive patients, 15 with communicating hydrocephalus (CH) and 16 with non-communicating hydrocephalus (NCH), were investigated before and after surgery using a 3D SPACE (sampling perfection with application optimised contrast using different flip-angle evolution) sequence. Two readers assessed CSF volume changes using 3D colour-encoded maps. The Evans index and postoperative volume changes of the lateral ventricles and sylvian fissures were quantified and statistically compared. Before surgery, sylvian fissure and brain ventricle volume differed significantly between CH and NCH (P = 0.001 and P = 0.025, respectively). After surgery, 3D colour-encoded maps allowed for the visual recognition of the CSF volume changes in all patients. The amounts of ventricle volume loss of CH and NCH patients were not significantly different (P = 0.30), whereas readjustment of the sylvian fissure volume was conflicting in CH and NCH patients (P < 0.001). The Evans index correlated with ventricle volume in NCH patients. 3D mapping of CSF volume changes is feasible providing a quantitative follow-up of patients with hydrocephalus. (orig.)

  11. Susceptibility contrast imaging of CO2-induced changes in the blood volume of the human brain

    DEFF Research Database (Denmark)

    Rostrup, Egill; Larsson, H B; Toft, P B

    1996-01-01

    PURPOSE: To investigate changes in the regional cerebral blood volume (rCBV) in human subjects during rest and hypercapnia by MR imaging, and to compare the results from contrast-enhanced and noncontrast-enhanced susceptibility-weighted imaging. MATERIAL AND METHODS: Five healthy volunteers (aged...... to be in accordance with results obtained by other methods. Noncontrast functional MR (fMR) imaging showed signal increases in gray matter, but also inconsistent changes in some white matter regions. CONCLUSION: In this experiment, contrast-enhanced imaging seemed to show a somewhat higher sensitivity towards changes...

  12. Exercise induced pulmonary, hepatic and splenic blood volume changes in diabetic subjects

    International Nuclear Information System (INIS)

    Mubashar, M.

    1993-01-01

    Exercise induced blood volume changes in visceral organs were determined by scintillation gamma camera imaging in 11 normal healthy male volunteers and 15 NIDDM male diabetics without clinical signs of neuropathy. After in-vivo labelling of red cells with Technetium-99m, the data was acquired in the supine position at rest and immediately after graded upright ergometer bicycle exercise. From rest to peak exercise, pulmonary blood volume increased 19% and 75% in normal volunteers of less than and more than 40 years of age respectively. A decrease of 18% and 42% was noted in the hepatic and splenic blood volume respectively, regardless of the age, in the normal subjects. In contrast to normals, the diabetic patients showed in response to peak exercise as compared to age-matched controls. A significant difference in the drop in pulmonary blood volume 82.37% and 90% was observed between diabetics of more than and less than 7 years duration respectively. The liver and spleen of the diabetic subjects revealed a lesser decrease of 87.6% and 71.33% respectively in response to peak stress in comparison to the age matched controls. The reduction in the hepatic and splenic blood volume was equally evident in diabetics of more than or less than 50 years of age and it was statistically nonsignificant. This study demonstrates that the normal pattern of redistribution of blood volume in response to maximum exercise in diabetics is altered such that there is restricted pulmonary perfusion and diminished vasoconstriction of the hepato splenic vascular bed and the changes in the pulmonary circulation are related to the duration of the diabetics rather than the age of the patient. (author)

  13. Residual limb fluid volume change and volume accommodation: Relationships to activity and self-report outcomes in people with trans-tibial amputation.

    Science.gov (United States)

    Sanders, Joan E; Youngblood, Robert T; Hafner, Brian J; Ciol, Marcia A; Allyn, Katheryn J; Gardner, David; Cagle, John C; Redd, Christian B; Dietrich, Colin R

    2018-02-01

    Fluctuations in limb volume degrade prosthesis fit and require users to accommodate changes using management strategies, such as donning and doffing prosthetic socks. To examine how activities and self-report outcomes relate to daily changes in residual limb fluid volume and volume accommodation. Standardized, two-part laboratory protocol with an interim observational period. Participants were classified as "accommodators" or "non-accommodators," based on self-report prosthetic sock use. Participants' residual limb fluid volume change was measured using a custom bioimpedance analyzer and a standardized in-laboratory activity protocol. Self-report health outcomes were assessed with the Socket Comfort Score and Prosthesis Evaluation Questionnaire. Activity was monitored while participants left the laboratory for at least 3 h. They then returned to repeat the bioimpedance test protocol. Twenty-nine people were enrolled. Morning-to-afternoon percent limb fluid volume change per hour was not strongly correlated to percent time weight-bearing or to self-report outcomes. As a group, non-accommodators ( n = 15) spent more time with their prosthesis doffed and reported better outcomes than accommodators. Factors other than time weight-bearing may contribute to morning-to-afternoon limb fluid volume changes and reported satisfaction with the prosthesis among trans-tibial prosthesis users. Temporary doffing may be a more effective and satisfying accommodation method than sock addition. Clinical relevance Practitioners should be mindful that daily limb fluid volume change and prosthesis satisfaction are not dictated exclusively by activity. Temporarily doffing the prosthesis may slow daily limb fluid volume loss and should be investigated as an alternative strategy to sock addition.

  14. Know your tools - concordance of different methods for measuring brain volume change after ischemic stroke

    Energy Technology Data Exchange (ETDEWEB)

    Yassi, Nawaf; Campbell, Bruce C.V.; Davis, Stephen M.; Bivard, Andrew [The University of Melbourne, Departments of Medicine and Neurology, Melbourne Brain Centre rate at The Royal Melbourne Hospital, Parkville, Victoria (Australia); Moffat, Bradford A.; Steward, Christopher; Desmond, Patricia M. [The University of Melbourne, Department of Radiology, The Royal Melbourne Hospital, Parkville (Australia); Churilov, Leonid [The University of Melbourne, The Florey Institute of Neurosciences and Mental Health, Parkville (Australia); Parsons, Mark W. [University of Newcastle and Hunter Medical Research Institute, Priority Research Centre for Translational Neuroscience and Mental Health, Newcastle (Australia)

    2015-07-15

    Longitudinal brain volume changes have been investigated in a number of cerebral disorders as a surrogate marker of clinical outcome. In stroke, unique methodological challenges are posed by dynamic structural changes occurring after onset, particularly those relating to the infarct lesion. We aimed to evaluate agreement between different analysis methods for the measurement of post-stroke brain volume change, and to explore technical challenges inherent to these methods. Fifteen patients with anterior circulation stroke underwent magnetic resonance imaging within 1 week of onset and at 1 and 3 months. Whole-brain as well as grey- and white-matter volume were estimated separately using both an intensity-based and a surface watershed-based algorithm. In the case of the intensity-based algorithm, the analysis was also performed with and without exclusion of the infarct lesion. Due to the effects of peri-infarct edema at the baseline scan, longitudinal volume change was measured as percentage change between the 1 and 3-month scans. Intra-class and concordance correlation coefficients were used to assess agreement between the different analysis methods. Reduced major axis regression was used to inspect the nature of bias between measurements. Overall agreement between methods was modest with strong disagreement between some techniques. Measurements were variably impacted by procedures performed to account for infarct lesions. Improvements in volumetric methods and consensus between methodologies employed in different studies are necessary in order to increase the validity of conclusions derived from post-stroke cerebral volumetric studies. Readers should be aware of the potential impact of different methods on study conclusions. (orig.)

  15. Know your tools - concordance of different methods for measuring brain volume change after ischemic stroke

    International Nuclear Information System (INIS)

    Yassi, Nawaf; Campbell, Bruce C.V.; Davis, Stephen M.; Bivard, Andrew; Moffat, Bradford A.; Steward, Christopher; Desmond, Patricia M.; Churilov, Leonid; Parsons, Mark W.

    2015-01-01

    Longitudinal brain volume changes have been investigated in a number of cerebral disorders as a surrogate marker of clinical outcome. In stroke, unique methodological challenges are posed by dynamic structural changes occurring after onset, particularly those relating to the infarct lesion. We aimed to evaluate agreement between different analysis methods for the measurement of post-stroke brain volume change, and to explore technical challenges inherent to these methods. Fifteen patients with anterior circulation stroke underwent magnetic resonance imaging within 1 week of onset and at 1 and 3 months. Whole-brain as well as grey- and white-matter volume were estimated separately using both an intensity-based and a surface watershed-based algorithm. In the case of the intensity-based algorithm, the analysis was also performed with and without exclusion of the infarct lesion. Due to the effects of peri-infarct edema at the baseline scan, longitudinal volume change was measured as percentage change between the 1 and 3-month scans. Intra-class and concordance correlation coefficients were used to assess agreement between the different analysis methods. Reduced major axis regression was used to inspect the nature of bias between measurements. Overall agreement between methods was modest with strong disagreement between some techniques. Measurements were variably impacted by procedures performed to account for infarct lesions. Improvements in volumetric methods and consensus between methodologies employed in different studies are necessary in order to increase the validity of conclusions derived from post-stroke cerebral volumetric studies. Readers should be aware of the potential impact of different methods on study conclusions. (orig.)

  16. Volume-of-change cone-beam CT for image-guided surgery

    International Nuclear Information System (INIS)

    Lee, Junghoon; Stayman, J Webster; Otake, Yoshito; Schafer, Sebastian; Zbijewski, Wojciech; Khanna, A Jay; Siewerdsen, Jeffrey H; Prince, Jerry L

    2012-01-01

    C-arm cone-beam CT (CBCT) can provide intraoperative 3D imaging capability for surgical guidance, but workflow and radiation dose are the significant barriers to broad utilization. One main reason is that each 3D image acquisition requires a complete scan with a full radiation dose to present a completely new 3D image every time. In this paper, we propose to utilize patient-specific CT or CBCT as prior knowledge to accurately reconstruct the aspects of the region that have changed by the surgical procedure from only a sparse set of x-rays. The proposed methods consist of a 3D–2D registration between the prior volume and a sparse set of intraoperative x-rays, creating digitally reconstructed radiographs (DRRs) from the registered prior volume, computing difference images by subtracting DRRs from the intraoperative x-rays, a penalized likelihood reconstruction of the volume of change (VOC) from the difference images, and finally a fusion of VOC reconstruction with the prior volume to visualize the entire surgical field. When the surgical changes are local and relatively small, the VOC reconstruction involves only a small volume size and a small number of projections, allowing less computation and lower radiation dose than is needed to reconstruct the entire surgical field. We applied this approach to sacroplasty phantom data obtained from a CBCT test bench and vertebroplasty data with a fresh cadaver acquired from a C-arm CBCT system with a flat-panel detector. The VOCs were reconstructed from a varying number of images (10–66 images) and compared to the CBCT ground truth using four different metrics (mean squared error, correlation coefficient, structural similarity index and perceptual difference model). The results show promising reconstruction quality with structural similarity to the ground truth close to 1 even when only 15–20 images were used, allowing dose reduction by the factor of 10–20. (paper)

  17. Improving the clinical correlation of multiple sclerosis black hole volume change by paired-scan analysis.

    Science.gov (United States)

    Tam, Roger C; Traboulsee, Anthony; Riddehough, Andrew; Li, David K B

    2012-01-01

    The change in T 1-hypointense lesion ("black hole") volume is an important marker of pathological progression in multiple sclerosis (MS). Black hole boundaries often have low contrast and are difficult to determine accurately and most (semi-)automated segmentation methods first compute the T 2-hyperintense lesions, which are a superset of the black holes and are typically more distinct, to form a search space for the T 1w lesions. Two main potential sources of measurement noise in longitudinal black hole volume computation are partial volume and variability in the T 2w lesion segmentation. A paired analysis approach is proposed herein that uses registration to equalize partial volume and lesion mask processing to combine T 2w lesion segmentations across time. The scans of 247 MS patients are used to compare a selected black hole computation method with an enhanced version incorporating paired analysis, using rank correlation to a clinical variable (MS functional composite) as the primary outcome measure. The comparison is done at nine different levels of intensity as a previous study suggests that darker black holes may yield stronger correlations. The results demonstrate that paired analysis can strongly improve longitudinal correlation (from -0.148 to -0.303 in this sample) and may produce segmentations that are more sensitive to clinically relevant changes.

  18. Early changes in volume and non-enhanced volume of acoustic neurinoma after stereotactic gamma-radiosurgery

    Energy Technology Data Exchange (ETDEWEB)

    Oyama, Hirofumi; Kobayashi, Tatsuya; Kida, Yoshihisa; Tanaka, Takayuki; Mori, Yoshimasa; Iwakoshi, Takayasu; Niwa, Masahiro; Kai, Osamu; Hirose, Mitsuhiko [Komaki City Hospital, Aichi (Japan)

    1994-09-01

    The effectiveness of stereotactic gamma-radiosurgery for treating acoustic neurinoma was evaluated by measuring the volumes of the tumor, non-enhanced tumor, and cerebellar edema in 13 patients with acoustic neurinoma who were followed up for 9 to 15 months (median 12.7 mos) after treatment. The tumor volume and non-enhanced volume tended to reach a maximum after 6 months, and cerebellar edema volume after 9 months, then decreased gradually thereafter. Hearing loss tended to increase gradually, but involvement of the facial nerve was transient. (author).

  19. Cerebral blood volume changes in cats with acute increased intracranial pressure

    International Nuclear Information System (INIS)

    Kondo, Takashi; Kano, Mitsumasa; Ikeda, Takuya.

    1984-01-01

    We measured the changes in cerebral blood volume in cats with increased intracranial pressure with a high-speed CT scanner, employing contrast effects by the iodine agent. In acute increased intracranial pressure caused by raising the extradural pressure by 20 mmHg, cerebral blood volume showed a significant decrease by 32% in comparison with that at normal intracranial pressure. There was also a tendency that a decline of iodine was delayed with time at increased intracranial pressure than that at normal pressure. This was supposed to be a delay of cerebral circulation due to venous congestion. This experimental model and measuring method provide the changes in CBV in the same individual without any tedious procedure, and therefore this is a reliable method with respect to precision. (author)

  20. Stereological brain volume changes in post-weaned socially isolated rats

    DEFF Research Database (Denmark)

    Fabricius, Katrine; Helboe, Lone; Steiniger-Brach, Björn

    2010-01-01

    Lister Hooded rats isolated from postnatal day 25 for 15 weeks. We observed the expected gender differences in total brain volume with males having larger brains than females. Further, we found that isolated males had significantly smaller brains than group-housed controls and larger lateral ventricles...... have evaluated the neuroanatomical changes in this animal model in comparison to changes seen in schizophrenia. In this study, we applied stereological volume estimates to evaluate the total brain, the ventricular system, and the pyramidal and granular cell layers of the hippocampus in male and female...... than controls. However, this was not seen in female rats. Isolated males had a significant smaller hippocampus, dentate gyrus and CA2/3 where isolated females had a significant smaller CA1 compared to controls. Thus, our results indicate that long-term isolation of male rats leads to neuroanatomical...

  1. Large electrically induced height and volume changes in poly(3,4- ethylenedioxythiophene) /poly(styrenesulfonate) thin films

    NARCIS (Netherlands)

    Charrier, D.S.H.; Janssen, R.A.J.; Kemerink, M.

    2010-01-01

    We demonstrate large, partly reversible height and volume changes of thin films of poly(3,4-ethylenedioxythiophene)/poly(styrenesulfonate) (PEDOT:PSS) on the anode of interdigitating gold electrodes under ambient conditions by applying an electrical bias. The height and volume changes were monitored

  2. Role of cerebral blood volume changes in brain specific-gravity measurements

    International Nuclear Information System (INIS)

    Picozzi, P.; Todd, N.V.; Crockard, A.H.

    1985-01-01

    Cerebral blood volume (CBV) was calculated in gerbils from specific-gravity (SG) changes between normal and saline-perfused brains. Furthermore, changes in CBV were investigated during ischemia using carbon-14-labeled dextran (MW 70,000) as an intravascular marker. Both data were used to evaluate the possible error due to a change in CBV on the measurement of ischemic brain edema by the SG method. The methodological error found was 0.0004 for a 100% CBV change. This error is insignificant, being less than the standard deviation in the SG measured for the gerbil cortex. Thus, CBV changes are not responsible for the SG variations observed during the first phase of ischemia. These variations are better explained as an increase of brain water content during ischemia

  3. Susceptibility contrast imaging of CO2-induced changes in the blood volume of the human brain

    DEFF Research Database (Denmark)

    Rostrup, Egill; Larsson, H B; Toft, P B

    1996-01-01

    PURPOSE: To investigate changes in the regional cerebral blood volume (rCBV) in human subjects during rest and hypercapnia by MR imaging, and to compare the results from contrast-enhanced and noncontrast-enhanced susceptibility-weighted imaging. MATERIAL AND METHODS: Five healthy volunteers (aged...... in cerebral hemodynamics than noncontrast-enhanced imaging. The results of the deconvolution analysis suggested that perfusion calculation by conventional tracer kinetic methods may be impracticable because of nonlinear effects in contrast-enhanced MR imaging....

  4. The change of volume of each hepatic segment in liver cirrhosis

    International Nuclear Information System (INIS)

    Arai, Kazunori; Takashima, Tsutomu; Matsui, Osamu; Kadoya, Masumi; Kameyama, Tomiaki; Nishijima, Hiroshi; Takanaka, Tsuyoshi; Gabata, Toshifumi

    1986-01-01

    We studied morphological changes of liver due to liver cirrhosis by evaluating the volume of liver and each hepatic segments (left lateral, left medial, right anterior, right posterior, and caudate lobe) divided using dynamic sequential CT during arterial portography. In liver cirrhosis, left lateral segment and caudate lobe were relatively enlarged, while right lobe and left medial segment showed significant shrinkage. But when posterior inferior right hepatic vein was evident on CT, right posterior segment did not shrink. (author)

  5. Realistic torso phantom for calibration of in-vivo transuranic-nuclide counting facilities

    Energy Technology Data Exchange (ETDEWEB)

    Shirotani, Takashi

    1988-11-01

    A realistic torso phantom with average body size of Japanese adult males has been developed for the calibration of counting systems used for in-vivo measurements of plutonium and other actinides. The phantom contains removable model organs (lungs, liver, kidneys and heart), model trachea and artificial rib cage, and also includes chest plates that can be placed over the chest to simulate wide range adipose/muscle ratio in the human chest. Tissue substitutes used in the phantom were made of polyurethane with different concentrations of ester of phosphoric acid. Model lungs were made of foamed polyurethane with small quantities of the additive, and the artificial rib cage was made of epoxy resin with calcium carbonate. The experimental data have shown that the phantom can be used as a standard phantom for the calibration.

  6. Toward anthropomimetic robotics: development, simulation, and control of a musculoskeletal torso.

    Science.gov (United States)

    Wittmeier, Steffen; Alessandro, Cristiano; Bascarevic, Nenad; Dalamagkidis, Konstantinos; Devereux, David; Diamond, Alan; Jäntsch, Michael; Jovanovic, Kosta; Knight, Rob; Marques, Hugo Gravato; Milosavljevic, Predrag; Mitra, Bhargav; Svetozarevic, Bratislav; Potkonjak, Veljko; Pfeifer, Rolf; Knoll, Alois; Holland, Owen

    2013-01-01

    Anthropomimetic robotics differs from conventional approaches by capitalizing on the replication of the inner structures of the human body, such as muscles, tendons, bones, and joints. Here we present our results of more than three years of research in constructing, simulating, and, most importantly, controlling anthropomimetic robots. We manufactured four physical torsos, each more complex than its predecessor, and developed the tools required to simulate their behavior. Furthermore, six different control approaches, inspired by classical control theory, machine learning, and neuroscience, were developed and evaluated via these simulations or in small-scale setups. While the obtained results are encouraging, we are aware that we have barely exploited the potential of the anthropomimetic design so far. But, with the tools developed, we are confident that this novel approach will contribute to our understanding of morphological computation and human motor control in the future.

  7. Are Torsos the Basis for Infants' Categorization of Cats Versus Dogs? A Reply to Vidic and Haaf (2004)

    Science.gov (United States)

    Quinn, Paul C.

    2005-01-01

    Vidic and Haaf (2004) questioned the idea that infants use head information to categorize cats as distinct from dogs (Quinn & Eimas, 1996) and argued instead that the torso region is important. However, only null results were observed in the critical test comparisons between modified and unmodified stimuli. In addition, a priori preferences for…

  8. Photoplethysmography for blood volumes and oxygenation changes during intermittent vascular occlusions.

    Science.gov (United States)

    Abay, T Y; Kyriacou, P A

    2018-06-01

    Photoplethysmography (PPG) is an optical technique that measures blood volume variations. The main application of dual-wavelength PPG is pulse oximetry, in which the arterial oxygen saturation (SpO[Formula: see text]) is calculated noninvasively. However, the PPG waveform contains other significant physiological information that can be used in conjunction to SpO[Formula: see text] for the assessment of oxygenation and blood volumes changes. This paper investigates the use of near infrared spectroscopy (NIRS) processing techniques for extracting relative concentration changes of oxygenated ([Formula: see text]HbO[Formula: see text]), reduced ([Formula: see text]HHb) and total haemoglobin ([Formula: see text]tHb) from dual-wavelength PPG signals during intermittent pressure-increasing vascular occlusions. A reflectance PPG sensor was attached on the left forearm of nineteen (n = 19) volunteers, along with a reference NIRS sensor positioned on the same forearm, above the left brachioradialis. The investigation protocol consisted of seven intermittent and pressure-increasing vascular occlusions. Relative changes in haemoglobin concentrations were obtained by applying the modified Beer-Lambert law to PPG signals, while oxygenation changes were estimated by the difference between red and infrared attenuations of DC PPGs (A[Formula: see text] = [Formula: see text]A[Formula: see text] - [Formula: see text]A[Formula: see text]) and by the conventional SpO[Formula: see text]. The [Formula: see text]HbO[Formula: see text], [Formula: see text]HHb, [Formula: see text]tHb from the PPG signals indicated significant changes in perfusion induced by either partial and complete occlusions (p < 0.05). The trends in the variables extracted from PPG showed good correlation with the same parameters measured by the reference NIRS monitor. Bland and Altman analysis of agreement between PPG and NIRS showed underestimation of the magnitude of changes by the PPG. A[Formula: see text

  9. Hippocampal volume changes in healthy subjects at risk of unipolar depression

    DEFF Research Database (Denmark)

    Baaré, William F C; Vinberg, Maj; Knudsen, Gitte M

    2010-01-01

    Unipolar depression is moderately heritable. It is unclear whether structural brain changes associated with unipolar depression are present in healthy persons at risk of the disorder. Here we investigated whether a genetic predisposition to unipolar depression is associated with structural brain...... changes. A priori, hippocampal volume reductions were hypothesized. Using a high-risk study design, magnetic resonance imaging brain scans were obtained from 59 healthy high-risk subjects having a co-twin with unipolar depression, and 53 healthy low-risk subjects without a first-degree family history...

  10. Changes with age in left ventricular function and volumes at rest and postexercise in postmenopausal women

    International Nuclear Information System (INIS)

    Yamada, Kiyoyasu; Isobe, Satoshi; Hirai, Makoto

    2006-01-01

    In postmenopausal women, it has been reported that the plasma estrogen levels diminish immediately after menopause, and that this phenomenon affects left ventricular (LV) function and volumes. However, the effects of age on LV function and volumes for a relatively short period in the postmenopausal women remain to be established. Electrocardiographically gated-myocardial single-photon emission computed tomography (SPECT) has recently provided accurate estimations of perfusion, cardiac systolic and diastolic functions. We investigated the age-related changes in LV function and volumes in postmenopausal women using electrocardiographically gated-myocardial scintigraphy. Twenty-two consecutive healthy postmenopausal women (mean age of 63.8±9.4 years, from 42 to 77 years) without cardiac disease underwent stress/rest technetium-99m tetrofosmin gated-myocardial SPECT with 16 frames per cardiac cycle at baseline and follow-up (1.0±0.3 years later). LV ejection fraction (LVEF) and LV volumes were calculated by quantitative gated SPECT (QGS) software. Fourier series were retained for the analysis of the volume curve. From this volume curve, we derived the following diastolic indices: peak filling rate (PFR) and time to PFR (TPFR). End-systolic volume index (ESVI) significantly decreased at postexercise (p=0.02) and tended to decrease at rest (p=0.06) from the baseline to the follow-up study. LVEF significantly increased at both postexercise (p=0.01) and rest (p=0.03) from the baseline to the follow-up study. The TPFR at rest tended to be prolonged from the baseline to the follow-up study (p=0.07). The absolute increase in LVEF at postexercise tended to decrease with age [4.8% (50s) vs. 3.4% (60s) vs. 1.2% (70s)]. An age-related change in cardiac performance is apparent at an approximately 1 year follow-up in postmenopausal women. In particular, the increase in LV systolic function tends to show the greatest value in the 50s subjects among the 3 generations. (author)

  11. Volume changes in Alzheimer's disease and mild cognitive impairment: cognitive associations

    International Nuclear Information System (INIS)

    Evans, Matthew C.; Barnes, Josephine; Nielsen, Casper; Clegg, Shona L.; Blair, Melanie; Douiri, Abdel; Boyes, Richard G.; Fox, Nick C.; Kim, Lois G.; Leung, Kelvin K.; Ourselin, Sebastien

    2010-01-01

    To assess the relationship between MRI-derived changes in whole-brain and ventricular volume with change in cognitive scores in Alzheimer's disease (AD), mild cognitive impairment (MCI) and control subjects. In total 131 control, 231 MCI and 99 AD subjects from the Alzheimer's Disease Neuroimaging Initiative (ADNI) cohort with T1-weighted volumetric MRIs from baseline and 12-month follow-up were used to derive volume changes. Mini mental state examination (MMSE), Alzheimer's disease assessment scale (ADAS)-cog and trails test changes were calculated over the same period. Brain atrophy rates and ventricular enlargement differed between subject groups (p < 0.0005) and in MCI and AD were associated with MMSE changes. Both measures were additionally associated with ADAS-cog and trails-B in MCI patients, and ventricular expansion was associated with ADAS-cog in AD patients. Brain atrophy (p < 0.0005) and ventricular expansion rates (p = 0.001) were higher in MCI subjects who progressed to AD within 12 months of follow-up compared with MCI subjects who remained stable. MCI subjects who progressed to AD within 12 months had similar atrophy rates to AD subjects. Whole-brain atrophy rates and ventricular enlargement differed between patient groups and healthy controls, and tracked disease progression and psychological decline, demonstrating their relevance as biomarkers. (orig.)

  12. Variations in gastric compliance induced by acute blood volume changes in anesthetized rats

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    Graça J.R.V.

    2002-01-01

    Full Text Available The impact of acute volume imbalances on gastric volume (GV was studied in anesthetized rats (250-300 g. After cervical and femoral vessel cannulation, a balloon catheter was positioned in the proximal stomach. The opposite end of the catheter was connected to a barostat with an electronic sensor coupled to a plethysmometer. A standard ionic solution was used to fill the balloon (about 3.0 ml and the communicating vessel system, and to raise the reservoir liquid level 4 cm above the animals' xiphoid appendix. Due to constant barostat pressure, GV values were considered to represent the gastric compliance index. All animals were monitored for 90 min. After a basal interval, they were randomly assigned to normovolemic, hypervolemic, hypovolemic or restored protocols. Data were compared by ANOVA followed by Bonferroni's test. Mean arterial pressure (MAP, central venous pressure (CVP and GV values did not change in normovolemic animals (N = 5. Hypervolemic animals (N = 12 were transfused at 0.5 ml/min with a suspension of red blood cells in Ringer-lactate solution with albumin (12.5 ml/kg, which reduced GV values by 11.3% (P0.05. MAP and CVP values increased (P<0.05 after hypervolemia but decreased (P<0.05 with hypovolemia. In conclusion, blood volume level modulates gastric compliance, turning the stomach into an adjustable reservoir, which could be part of the homeostatic process to balance blood volume.

  13. A voxel-based morphometry study of brain volume changes in patients with neuromyelitis optica

    International Nuclear Information System (INIS)

    Duan Yunyun; Liu Yaou; Liang Peipeng; Huang Jing; Ren Zhuoqiong; Ye Jing; Dong Huiqing; Chen Hai; Li Kuncheng

    2012-01-01

    Objective: To detect changes of regional grey matter and white matter volume in patients of neuromyelitis optica (NMO) by voxel-based morphometry (VBM), and investigate its relationship with clinical variables. Methods: Conventional magnetic resonance imaging (MRI) and structural three-dimensional MRI were obtained from 20 NMO and 20 sex-and age-matched healthy volunteers. The comparison of grey matter and white matter volume between the two groups was analyzed by VBM tools of statistical parametric mapping (SPM) 5. Pearson correlation analysis was used to assess correlations between regional volume decrease and disease duration and expanded disability status scale (EDSS) scores in NMO patients. Results: Compared with normal controls, NMO patients had grey matter atrophy in several cortical regions, such as right inferior frontal gyrus (cluster size 514), left superior temporal gyrus (282), right middle temporal gyrus (229) and right insula (211) (t=3.58-5.11, AlphaSim corrected, P<0.05). White matter atrophy was found in several subcortical regions in NMO patients, such as right precentral and postcentral gyrus (cluster size 457, 110), left middle frontal gyrus (285), and right inferior parietal lobule (231) (t=2.90-4.25, AlphaSim corrected, P<0.05). Grey matter and white matter volume loss were not significantly correlated with clinical duration or EDSS score in NMO. Conclusion: By means of VBM, regional atrophy of grey matter and white matter is found in NMO patients, which may provide evidence for brain structural abnormality in NMO. (authors)

  14. Dynamic volume changes in astrocytes are an intrinsic phenomenon mediated by bicarbonate ion flux.

    Directory of Open Access Journals (Sweden)

    Clare M Florence

    Full Text Available Astrocytes, the major type of non-neuronal cells in the brain, play an important functional role in extracellular potassium ([K(+](o and pH homeostasis. Pathological brain states that result in [K(+](o and pH dysregulation have been shown to cause astrocyte swelling. However, whether astrocyte volume changes occur under physiological conditions is not known. In this study we used two-photon imaging to visualize real-time astrocyte volume changes in the stratum radiatum of the hippocampus CA1 region. Astrocytes were observed to swell by 19.0±0.9% in response to a small physiological increase in the concentration of [K(+](o (3 mM. Astrocyte swelling was mediated by the influx of bicarbonate (HCO(3- ions as swelling was significantly decreased when the influx of HCO(3- was reduced. We found: 1 in HCO(3- free extracellular solution astrocytes swelled by 5.4±0.7%, 2 when the activity of the sodium-bicarbonate cotransporter (NBC was blocked the astrocytes swelled by 8.3±0.7%, and 3 in the presence of an extracellular carbonic anhydrase (CA inhibitor astrocytes swelled by 11.4±0.6%. Because a significant HCO(3- efflux is known to occur through the γ-amino-butyric acid (GABA channel, we performed a series of experiments to determine if astrocytes were capable of HCO(3- mediated volume shrinkage with GABA channel activation. Astrocytes were found to shrink -7.7±0.5% of control in response to the GABA(A channel agonist muscimol. Astrocyte shrinkage from GABA(A channel activation was significantly decreased to -5.0±0.6% of control in the presence of the membrane-permeant CA inhibitor acetazolamide (ACTZ. These dynamic astrocyte volume changes may represent a previously unappreciated yet fundamental mechanism by which astrocytes regulate physiological brain functioning.

  15. Significance of breast boost volume changes during radiotherapy in relation to current clinical interobserver variations

    International Nuclear Information System (INIS)

    Hurkmans, Coen; Admiraal, Marjan; Sangen, Maurice van der; Dijkmans, Ingrid

    2009-01-01

    Background and purpose: Nowadays, many departments introduce CT images for breast irradiation techniques, aiming to obtain a better accuracy in the definition of the relevant target volumes. However, the definition of the breast boost volume based on CT images requires further investigation, because it may not only vary between observers, but it may also change during the course of treatment. This study aims to quantify the variability of the CT based visible boost volume (VBV) during the course of treatment in relation to the variability between observers. Materials and methods: Ten patients with stage T1-2 invasive breast cancer treated with breast conservative surgery and post surgical radiotherapy were included in this study. In addition to the regular planning CT which is obtained several days prior to radiotherapy, three additional CT scans were acquired 3, 5 and 7 weeks after the planning CT scan. Four radiation oncologists delineated the VBV in all scans. Conformity of the delineations was analysed both between observers, and between scans taken at different periods of the radiotherapy treatment. Results: The VBV averaged over all patients decreased during the course of the treatment from an initial 40 cm 3 to 28 cm 3 , 27 cm 3 and 25 cm 3 after 3, 5 and 7 weeks, respectively. Assuming the VBV to be spherical, this corresponds to a reduction in diameter of 5-6 mm. More detailed analysis revealed that this reduction was more pronounced when radiotherapy started within 30 days after surgery. These boost volume changes over time were found to be significant (p = 0.02) even in the presence of interobserver variations. Moreover, the conformity index (CI) for the volume changes was of the same magnitude as the conformity index for the interobserver variation (0.25 and 0.31, respectively). Conclusions: Breast boost volume variations during a course of radiotherapy are significant in relation to current clinical interobserver variations. This is an important

  16. International conference on the role of the polar regions in global change: Proceedings. Volume 2

    Energy Technology Data Exchange (ETDEWEB)

    Weller, G.; Wilson, C.L.; Severin, B.A.B. [eds.

    1991-12-01

    The International Conference on the Role of the Polar Regions in Global Change took place on the campus of the University of Alaska Fairbanks on June 11--15, 1990. The goal of the conference was to define and summarize the state of knowledge on the role of the polar regions in global change, and to identify gaps in knowledge. To this purpose experts in a wide variety of relevant disciplines were invited to present papers and hold panel discussions. While there are numerous conferences on global change, this conference dealt specifically with the polar regions which occupy key positions in the global system. These two volumes of conference proceedings include papers on (1) detection and monitoring of change; (2) climate variability and climate forcing; (3) ocean, sea ice, and atmosphere interactions and processes; and (4) effects on biota and biological feedbacks; (5) ice sheet, glacier and permafrost responses and feedbacks, (6) paleoenvironmental studies; and, (7) aerosol and trace gases.

  17. International conference on the role of the polar regions in global change: Proceedings. Volume 1

    Energy Technology Data Exchange (ETDEWEB)

    Weller, G.; Wilson, C.L.; Severin, B.A.B. [eds.

    1991-12-01

    The International Conference on the Role of the Polar Regions in Global Change took place on the campus of the University of Alaska Fairbanks on June 11--15, 1990. The goal of the conference was to define and summarize the state of knowledge on the role of the polar regions in global change, and to identify gaps in knowledge. To this purpose experts in a wide variety of relevant disciplines were invited to present papers and hold panel discussions. While there are numerous conferences on global change, this conference dealt specifically with polar regions which occupy key positions in the global system. These two volumes of conference proceedings include papers on (1) detection and monitoring of change; (2) climate variability and climate forcing; (3) ocean, sea ice, and atmosphere interactions and processes; (4) effects on biota and biological feedbacks; (5) ice sheet, glacier and permafrost responses and feedbacks; (6) paleoenvironmental studies; and, (7) aerosols and trace gases.

  18. Structural and volume changes and their correlation in electron irradiated alkali silicate glasses

    International Nuclear Information System (INIS)

    Gavenda, Tadeáš; Gedeon, Ondrej; Jurek, Karel

    2017-01-01

    Highlights: • Volume changes were correlated with both incubation dose and Raman spectra. • Irradiation decreases Si-O-Si angle and increases the amount of three-membered rings. • Levelling of the pits depends on the dose below and above incubation dose. • Restoration of the original structure was limited to low-frequency region. - Abstract: Two binary alkali silicate glasses (15K 2 O·85SiO 2 – denoted as K15 and 15Li 2 O·85SiO 2 – denoted as Li15) were irradiated by 50 keV electron beams with doses within the range of 2.1–15.9 kC/m 2 . Volume changes induced by electron irradiation were monitored by means of Atomic Force Microscopy (AFM). Raman spectra were taken from the irradiated spots to observe structural changes. Volume compaction observed at lower doses was correlated with the increase of the D2 peak. Volume expansion at higher doses was related to migration of alkali ions. Irradiated glasses were annealed at 400 °C and 500 °C for 60 min. After annealing irradiated spots were again examined by AFM and Raman spectroscopy in order to determine volume and structural relaxation of radiation induced changes. Annealing at higher temperatures resulted in the levelling of the pits created by irradiation, but only for doses below incubation dose. The pits created by doses above incubation dose were not levelled. Annealing caused decrease of D2 peak and shift of the Si-O-Si vibrations band in direction to original structure. Low-frequency region of annealed Li15 glass was undistinguishable from that of pristine glass, while annealing of K15 glass did not result in the full reversion to the original shape. The differences between glasses were attributed to higher T g of K15 glass. Q-motives bands of both glasses were not completely restored after annealing due to the absence of alkali ions.

  19. Structural and volume changes and their correlation in electron irradiated alkali silicate glasses

    Energy Technology Data Exchange (ETDEWEB)

    Gavenda, Tadeáš, E-mail: gavendat@vscht.cz [Department of Glass and Ceramics, University of Chemical Technology, Technicka 5, CZ-166 28 Prague (Czech Republic); Gedeon, Ondrej [Department of Glass and Ceramics, University of Chemical Technology, Technicka 5, CZ-166 28 Prague (Czech Republic); Jurek, Karel [Institute of Physics, Academy of the Czech Republic, Na Slovance 2, CZ-182 21 Prague (Czech Republic)

    2017-04-15

    Highlights: • Volume changes were correlated with both incubation dose and Raman spectra. • Irradiation decreases Si-O-Si angle and increases the amount of three-membered rings. • Levelling of the pits depends on the dose below and above incubation dose. • Restoration of the original structure was limited to low-frequency region. - Abstract: Two binary alkali silicate glasses (15K{sub 2}O·85SiO{sub 2} – denoted as K15 and 15Li{sub 2}O·85SiO{sub 2} – denoted as Li15) were irradiated by 50 keV electron beams with doses within the range of 2.1–15.9 kC/m{sup 2}. Volume changes induced by electron irradiation were monitored by means of Atomic Force Microscopy (AFM). Raman spectra were taken from the irradiated spots to observe structural changes. Volume compaction observed at lower doses was correlated with the increase of the D2 peak. Volume expansion at higher doses was related to migration of alkali ions. Irradiated glasses were annealed at 400 °C and 500 °C for 60 min. After annealing irradiated spots were again examined by AFM and Raman spectroscopy in order to determine volume and structural relaxation of radiation induced changes. Annealing at higher temperatures resulted in the levelling of the pits created by irradiation, but only for doses below incubation dose. The pits created by doses above incubation dose were not levelled. Annealing caused decrease of D2 peak and shift of the Si-O-Si vibrations band in direction to original structure. Low-frequency region of annealed Li15 glass was undistinguishable from that of pristine glass, while annealing of K15 glass did not result in the full reversion to the original shape. The differences between glasses were attributed to higher T{sub g} of K15 glass. Q-motives bands of both glasses were not completely restored after annealing due to the absence of alkali ions.

  20. Glacier Volume Change Estimation Using Time Series of Improved Aster Dems

    Science.gov (United States)

    Girod, Luc; Nuth, Christopher; Kääb, Andreas

    2016-06-01

    Volume change data is critical to the understanding of glacier response to climate change. The Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) system embarked on the Terra (EOS AM-1) satellite has been a unique source of systematic stereoscopic images covering the whole globe at 15m resolution and at a consistent quality for over 15 years. While satellite stereo sensors with significantly improved radiometric and spatial resolution are available to date, the potential of ASTER data lies in its long consistent time series that is unrivaled, though not fully exploited for change analysis due to lack of data accuracy and precision. Here, we developed an improved method for ASTER DEM generation and implemented it in the open source photogrammetric library and software suite MicMac. The method relies on the computation of a rational polynomial coefficients (RPC) model and the detection and correction of cross-track sensor jitter in order to compute DEMs. ASTER data are strongly affected by attitude jitter, mainly of approximately 4 km and 30 km wavelength, and improving the generation of ASTER DEMs requires removal of this effect. Our sensor modeling does not require ground control points and allows thus potentially for the automatic processing of large data volumes. As a proof of concept, we chose a set of glaciers with reference DEMs available to assess the quality of our measurements. We use time series of ASTER scenes from which we extracted DEMs with a ground sampling distance of 15m. Our method directly measures and accounts for the cross-track component of jitter so that the resulting DEMs are not contaminated by this process. Since the along-track component of jitter has the same direction as the stereo parallaxes, the two cannot be separated and the elevations extracted are thus contaminated by along-track jitter. Initial tests reveal no clear relation between the cross-track and along-track components so that the latter seems not to be

  1. GLACIER VOLUME CHANGE ESTIMATION USING TIME SERIES OF IMPROVED ASTER DEMS

    Directory of Open Access Journals (Sweden)

    L. Girod

    2016-06-01

    Full Text Available Volume change data is critical to the understanding of glacier response to climate change. The Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER system embarked on the Terra (EOS AM-1 satellite has been a unique source of systematic stereoscopic images covering the whole globe at 15m resolution and at a consistent quality for over 15 years. While satellite stereo sensors with significantly improved radiometric and spatial resolution are available to date, the potential of ASTER data lies in its long consistent time series that is unrivaled, though not fully exploited for change analysis due to lack of data accuracy and precision. Here, we developed an improved method for ASTER DEM generation and implemented it in the open source photogrammetric library and software suite MicMac. The method relies on the computation of a rational polynomial coefficients (RPC model and the detection and correction of cross-track sensor jitter in order to compute DEMs. ASTER data are strongly affected by attitude jitter, mainly of approximately 4 km and 30 km wavelength, and improving the generation of ASTER DEMs requires removal of this effect. Our sensor modeling does not require ground control points and allows thus potentially for the automatic processing of large data volumes. As a proof of concept, we chose a set of glaciers with reference DEMs available to assess the quality of our measurements. We use time series of ASTER scenes from which we extracted DEMs with a ground sampling distance of 15m. Our method directly measures and accounts for the cross-track component of jitter so that the resulting DEMs are not contaminated by this process. Since the along-track component of jitter has the same direction as the stereo parallaxes, the two cannot be separated and the elevations extracted are thus contaminated by along-track jitter. Initial tests reveal no clear relation between the cross-track and along-track components so that the latter

  2. Acute extracellular fluid volume changes increase ileocolonic resistance to saline flow in anesthetized dogs

    Directory of Open Access Journals (Sweden)

    Santiago Jr. A.T.

    1997-01-01

    Full Text Available We determined the effect of acute extracellular fluid volume changes on saline flow through 4 gut segments (ileocolonic, ileal, ileocolonic sphincter and proximal colon, perfused at constant pressure in anesthetized dogs. Two different experimental protocols were used: hypervolemia (iv saline infusion, 0.9% NaCl, 20 ml/min, volume up to 5% body weight and controlled hemorrhage (up to a 50% drop in mean arterial pressure. Mean ileocolonic flow (N = 6 was gradually and significantly decreased during the expansion (17.1%, P<0.05 and expanded (44.9%, P<0.05 periods while mean ileal flow (N = 7 was significantly decreased only during the expanded period (38%, P<0.05. Mean colonic flow (N = 7 was decreased during expansion (12%, P<0.05 but returned to control levels during the expanded period. Mean ileocolonic sphincter flow (N = 6 was not significantly modified. Mean ileocolonic flow (N = 10 was also decreased after hemorrhage (retracted period by 17% (P<0.05, but saline flow was not modified in the other separate circuits (N = 6, 5 and 4 for ileal, ileocolonic sphincter and colonic groups, respectively. The expansion effect was blocked by atropine (0.5 mg/kg, iv both on the ileocolonic (N = 6 and ileal (N = 5 circuits. Acute extracellular fluid volume retraction and expansion increased the lower gastrointestinal resistances to saline flow. These effects, which could physiologically decrease the liquid volume being supplied to the colon, are possible mechanisms activated to acutely balance liquid volume deficit and excess.

  3. Effect of Bcl-2 rs956572 polymorphism on age-related gray matter volume changes.

    Directory of Open Access Journals (Sweden)

    Mu-En Liu

    Full Text Available The anti-apoptotic protein B-cell CLL/lymphoma 2 (Bcl-2 gene is a major regulator of neural plasticity and cellular resilience. Recently, the Bcl-2 rs956572 single nucleotide polymorphism was proposed to be a functional allelic variant that modulates cellular vulnerability to apoptosis. Our cross-sectional study investigated the genetic effect of this Bcl-2 polymorphism on age-related decreases in gray matter (GM volume across the adult lifespan. Our sample comprised 330 healthy volunteers (191 male, 139 female with a mean age of 56.2±22.0 years (range: 21-92. Magnetic resonance imaging and genotyping of the Bcl-2 rs956572 were performed for each participant. The differences in regional GM volumes between G homozygotes and A-allele carriers were tested using optimized voxel-based morphometry. The association between the Bcl-2 rs956572 polymorphism and age was a predictor of regional GM volumes in the right cerebellum, bilateral lingual gyrus, right middle temporal gyrus, and right parahippocampal gyrus. We found that the volume of these five regions decreased with increasing age (all P<.001. Moreover, the downward slope was steeper among the Bcl-2 rs956572 A-allele carriers than in the G-homozygous participants. Our data provide convergent evidence for the genetic effect of the Bcl-2 functional allelic variant in brain aging. The rs956572 G-allele, which is associated with significantly higher Bcl-2 protein expression and diminished cellular sensitivity to stress-induced apoptosis, conferred a protective effect against age-related changes in brain GM volume, particularly in the cerebellum.

  4. Evaluation of the effect of prostate volume change on tumor control probability in LDR brachytherapy.

    Science.gov (United States)

    Knaup, Courtney; Mavroidis, Panayiotis; Stathakis, Sotirios; Smith, Mark; Swanson, Gregory; Papanikolaou, Niko

    2011-09-01

    This study evaluates low dose-rate brachytherapy (LDR) prostate plans to determine the biological effect of dose degradation due to prostate volume changes. In this study, 39 patients were evaluated. Pre-implant prostate volume was determined using ultrasound. These images were used with the treatment planning system (Nucletron Spot Pro 3.1(®)) to create treatment plans using (103)Pd seeds. Following the implant, patients were imaged using CT for post-implant dosimetry. From the pre and post-implant DVHs, the biologically equivalent dose and the tumor control probability (TCP) were determined using the biologically effective uniform dose. The model used RBE = 1.75 and α/β = 2 Gy. The prostate volume changed between pre and post implant image sets ranged from -8% to 110%. TCP and the mean dose were reduced up to 21% and 56%, respectively. TCP is observed to decrease as the mean dose decreases to the prostate. The post-implant tumor dose was generally observed to decrease, compared to the planned dose. A critical uniform dose of 130 Gy was established. Below this dose, TCP begins to fall-off. It was also determined that patients with a small prostates were more likely to suffer TCP decrease. The biological effect of post operative prostate growth due to operative trauma in LDR was evaluated using the concept. The post-implant dose was lower than the planned dose due to an increase of prostate volume post-implant. A critical uniform dose of 130 Gy was determined, below which TCP begun to decline.

  5. A dual-Kinect approach to determine torso surface motion for respiratory motion correction in PET

    Energy Technology Data Exchange (ETDEWEB)

    Heß, Mirco, E-mail: mirco.hess@uni-muenster.de; Büther, Florian; Dawood, Mohammad; Schäfers, Klaus P. [European Institute for Molecular Imaging, University of Münster, Münster 48149 (Germany); Gigengack, Fabian [European Institute for Molecular Imaging, University of Münster, Münster 48149, Germany and Department of Mathematics and Computer Science, University of Münster, Münster 48149 (Germany)

    2015-05-15

    Purpose: Respiratory gating is commonly used to reduce blurring effects and attenuation correction artifacts in positron emission tomography (PET). Established clinically available methods that employ body-attached hardware for acquiring respiration signals rely on the assumption that external surface motion and internal organ motion are well correlated. In this paper, the authors present a markerless method comprising two Microsoft Kinects for determining the motion on the whole torso surface and aim to demonstrate its validity and usefulness—including the potential to study the external/internal correlation and to provide useful information for more advanced correction approaches. Methods: The data of two Kinects are used to calculate 3D representations of a patient’s torso surface with high spatial coverage. Motion signals can be obtained for any position by tracking the mean distance to a virtual camera with a view perpendicular to the surrounding surface. The authors have conducted validation experiments including volunteers and a moving high-precision platform to verify the method’s suitability for providing meaningful data. In addition, the authors employed it during clinical {sup 18}F-FDG-PET scans and exemplarily analyzed the acquired data of ten cancer patients. External signals of abdominal and thoracic regions as well as data-driven signals were used for gating and compared with respect to detected displacement of present lesions. Additionally, the authors quantified signal similarities and time shifts by analyzing cross-correlation sequences. Results: The authors’ results suggest a Kinect depth resolution of approximately 1 mm at 75 cm distance. Accordingly, valid signals could be obtained for surface movements with small amplitudes in the range of only few millimeters. In this small sample of ten patients, the abdominal signals were better suited for gating the PET data than the thoracic signals and the correlation of data-driven signals was

  6. A dual-Kinect approach to determine torso surface motion for respiratory motion correction in PET

    International Nuclear Information System (INIS)

    Heß, Mirco; Büther, Florian; Dawood, Mohammad; Schäfers, Klaus P.; Gigengack, Fabian

    2015-01-01

    Purpose: Respiratory gating is commonly used to reduce blurring effects and attenuation correction artifacts in positron emission tomography (PET). Established clinically available methods that employ body-attached hardware for acquiring respiration signals rely on the assumption that external surface motion and internal organ motion are well correlated. In this paper, the authors present a markerless method comprising two Microsoft Kinects for determining the motion on the whole torso surface and aim to demonstrate its validity and usefulness—including the potential to study the external/internal correlation and to provide useful information for more advanced correction approaches. Methods: The data of two Kinects are used to calculate 3D representations of a patient’s torso surface with high spatial coverage. Motion signals can be obtained for any position by tracking the mean distance to a virtual camera with a view perpendicular to the surrounding surface. The authors have conducted validation experiments including volunteers and a moving high-precision platform to verify the method’s suitability for providing meaningful data. In addition, the authors employed it during clinical 18 F-FDG-PET scans and exemplarily analyzed the acquired data of ten cancer patients. External signals of abdominal and thoracic regions as well as data-driven signals were used for gating and compared with respect to detected displacement of present lesions. Additionally, the authors quantified signal similarities and time shifts by analyzing cross-correlation sequences. Results: The authors’ results suggest a Kinect depth resolution of approximately 1 mm at 75 cm distance. Accordingly, valid signals could be obtained for surface movements with small amplitudes in the range of only few millimeters. In this small sample of ten patients, the abdominal signals were better suited for gating the PET data than the thoracic signals and the correlation of data-driven signals was found

  7. Changes in sediment volume in Alder Lake, Nisqually River Basin, Washington, 1945-2011

    Science.gov (United States)

    Czuba, Jonathan A.; Olsen, Theresa D.; Czuba, Christiana R.; Magirl, Christopher S.; Gish, Casey C.

    2012-01-01

    The Nisqually River drains the southwest slopes of Mount Rainier, a glaciated stratovolcano in the Cascade Range of western Washington. The Nisqually River was impounded behind Alder Dam when the dam was completed in 1945 and formed Alder Lake. This report quantifies the volume of sediment deposited by the Nisqually and Little Nisqually Rivers in their respective deltas in Alder Lake since 1945. Four digital elevation surfaces were generated from historical contour maps from 1945, 1956, and 1985, and a bathymetric survey from 2011. These surfaces were used to compute changes in sediment volume since 1945. Estimates of the volume of sediment deposited in Alder Lake between 1945 and 2011 were focused in three areas: (1) the Nisqually River delta, (2) the main body of Alder Lake, along a 40-meter wide corridor of the pre-dam Nisqually River, and (3) the Little Nisqually River delta. In each of these areas the net deposition over the 66-year period was 42,000,000 ± 4,000,000 cubic meters (m3), 2,000,000 ± 600,000 m3, and 310,000 ± 110,000 m3, respectively. These volumes correspond to annual rates of accumulation of 630,000 ± 60,000 m3/yr, 33,000 ± 9,000 m3/yr, and 4,700 ± 1,600 m3/yr, respectively. The annual sediment yield of the Nisqually (1,100 ± 100 cubic meters per year per square kilometer [(m3/yr)/km2]) and Little Nisqually River basins [70 ± 24 (m3/yr)/km2] provides insight into the yield of two basins with different land cover and geomorphic processes. These estimates suggest that a basin draining a glaciated stratovolcano yields approximately 15 times more sediment than a basin draining forested uplands in the Cascade Range. Given the cumulative net change in sediment volume in the Nisqually River delta in Alder Lake, the total capacity of Alder Lake since 1945 decreased about 3 percent by 1956, 8 percent by 1985, and 15 percent by 2011.

  8. Volume Changes After Stereotactic LINAC Radiotherapy in Vestibular Schwannoma: Control Rate and Growth Patterns

    International Nuclear Information System (INIS)

    Langenberg, Rick van de; Dohmen, Amy J.C.; Bondt, Bert J. de; Nelemans, Patty J.; Baumert, Brigitta G.; Stokroos, Robert J.

    2012-01-01

    Purpose: The purpose of this study was to evaluate the control rate of vestibular schwannomas (VS) after treatment with linear accelerator (LINAC)-based stereotactic radiosurgery (SRS) or radiotherapy (SRT) by using a validated volumetric measuring tool. Volume-based studies on prognosis after LINAC-based SRS or SRT for VS are reported scarcely. In addition, growth patterns and risk factors predicting treatment failure were analyzed. Materials and Methods: Retrospectively, 37 VS patients treated with LINAC based SRS or SRT were analyzed. Baseline and follow-up magnetic resonance imaging scans were analyzed with volume measurements on contrast enhanced T1-weighted magnetic resonance imaging. Absence of intervention after radiotherapy was defined as “no additional intervention group, ” absence of radiological growth was defined as “radiological control group. ” Significant growth was defined as a volume change of 19.7% or more, as calculated in a previous study. Results: The cumulative 4-year probability of no additional intervention was 96.4% ± 0.03; the 4-year radiological control probability was 85.4% ± 0.1). The median follow-up was 40 months. Overall, shrinkage was seen in 65%, stable VS in 22%, and growth in 13%. In 54% of all patients, transient swelling was observed. No prognostic factors were found regarding VS growth. Previous treatment and SRS were associated with transient swelling significantly. Conclusions: Good control rates are reported for LINAC based SRS or SRT in VS, in which the lower rate of radiological growth control is attributed to the use of the more sensitive volume measurements. Transient swelling after radiosurgery is a common phenomenon and should not be mistaken for treatment failure. Previous treatment and SRS were significantly associated with transient swelling.

  9. Early age volume changes in concrete due to chemical shrinkage of cement paste

    Directory of Open Access Journals (Sweden)

    Ebensperger, L.

    1991-12-01

    Full Text Available Unrestrained early age volume changes due to chemical shrinkage in cement pastes, mortars and concretes have been determined. The measurements were performed on sealed and unsealed samples which were stored under water. The chemical shrinkage of unsealed specimens represents the amount of absorbed water due to the chemical reaction of the cement It depends only on the cement content of the sample and does not lead to changes of the external dimensions. However the chemical shrinkage of sealed specimens is connected with a real volume change due to self-desiccation and the effect of internal pressures. The shrinkage depends in this case on the restraining effect of coarse aggregates as well as the cement content. The chemical shrinkage measured on sealed concretes was much higher than the one expected to ocurr on concretes, because normally an equalization of pressure takes place to some extent in the interior of the concrete. The use of expansive additives showed that they may compensate the chemical shrinkage, but its dosage is very sensitive and should be defined exactly for each case particularly.

    Se han determinado los cambios volumétricos que ocurren en pastas de cemento, morteros y hormigones a edad temprana debido al efecto de la retracción química. Las mediciones se realizaron en probetas selladas y no selladas sumergidas bajo agua. La retracción química en probetas no selladas representa la cantidad de agua absorbida debido a la reacción química del cemento. Depende solamente del contenido de cemento de la probeta y no produce ningún cambio en las dimensiones de la probeta. Por el contrario, la retracción química en probetas selladas está relacionada con un cambio volumétrico real debido al efecto de la autodesecación y presiones internas. La retracción en este caso depende tanto de la restricción que imponen los áridos, como del contenido de cemento. La retracción química medida en hormigones sellados

  10. Changes in gray matter volume after microsurgical lumbar discectomy: A longitudinal analysis

    Directory of Open Access Journals (Sweden)

    Michael eLuchtmann

    2015-02-01

    Full Text Available People around the world suffer chronic lower back pain. Because spine imaging often does not explain the degree of perceived pain reported by patients, the role of the processing of nociceptor signals in the brain as the basis of pain perception is gaining increased attention. Modern neuroimaging techniques (including functional and morphometric methods have produced results that suggest which brain areas may play a crucial role in the perception of acute and chronic pain. In this study, we examined twelve patients with chronic low back pain and sciatica, both resulting from lumbar disc herniation. Structural magnetic resonance imaging (MRI of the brain was performed one day prior to and about four weeks after microsurgical lumbar discectomy. The subsequent MRI revealed an increase in gray matter volume in the basal ganglia but a decrease in volume in the hippocampus, which suggests the complexity of the network that involves movement, pain processing, and aspects of memory. Interestingly, volume changes in the hippocampus were significantly correlated to preoperative pain intensity but not to the duration of chronic pain. Mapping structural changes of the brain that result from lumbar disc herniation has the potential to enhance our understanding of the neuropathology of chronic low back pain and sciatica and therefore may help to optimize the decisions we make about conservative and surgical treatments in the future. The possibility of illuminating more of the details of central pain processing in lumbar disc herniation, as well as the accompanying personal and economic impact of pain relief worldwide, calls for future large-scale clinical studies.

  11. Intra-aortic balloon shape change: effects on volume displacement during inflation and deflation.

    Science.gov (United States)

    Khir, Ashraf William; Bruti, Gianpaolo

    2013-07-01

    It has been observed that operating the intra-aortic balloon at an angle to the horizontal resulted in a reduction of the volume displaced toward the coronary arteries and compromised afterload reduction. Therefore, the aim of this work is to examine whether changing the current balloon shape, which has not been altered for 40 years, could compensate for the negative hemodynamic effects due to angulation. We tested two tapered balloons, increasing diameter (TID) and decreasing diameter (TDD), and compared the results with those obtained from a standard cylindrical balloon. The balloons were tested in vitro at 60 beats/min and a static pressure of 90 mm Hg. The balloons were operated at four angles (0°, 20°, 30°, 45°), and the pressure at three locations along the balloon (base, middle, and tip) was also measured. Flow rate upstream of the tip of the balloon was also measured to indicate the flow displaced toward the coronary circulation. The relative volume displaced toward (VUTVi) and suctioned away from (VUTVd) the simulated ascending aorta, during inflation and deflation, respectively, is reduced when a standard cylindrical balloon is operated at an angle to the horizontal. The TDD provided the greatest VUTVi and also produced the largest pulse pressure during deflation. Although the TID provided less VUTVi and VUTVd at smaller angles, it was not markedly affected by the change of angle. According to these results, different balloon shapes analyzed, with comparable volume to that of a cylindrical balloon, produced greater inflation and deflation benefits, at the horizontal and at a range of angles to the horizontal. Further investigations are required to optimize the shape of the tapered balloons to fit into the available physiological space. © 2013 Wiley Periodicals, Inc. and International Center for Artificial Organs and Transplantation.

  12. Evaluation of the effect of prostate volume change on tumor control probability in LDR brachytherapy

    Directory of Open Access Journals (Sweden)

    Courtney Knaup

    2011-09-01

    Full Text Available Purpose: This study evaluates low dose-rate brachytherapy (LDR prostate plans to determine the biological effectof dose degradation due to prostate volume changes. Material and methods: In this study, 39 patients were evaluated. Pre-implant prostate volume was determinedusing ultrasound. These images were used with the treatment planning system (Nucletron Spot Pro 3.1® to create treatmentplans using 103Pd seeds. Following the implant, patients were imaged using CT for post-implant dosimetry. Fromthe pre and post-implant DVHs, the biologically equivalent dose and the tumor control probability (TCP were determinedusing the biologically effective uniform dose. The model used RBE = 1.75 and α/β = 2 Gy. Results: The prostate volume changed between pre and post implant image sets ranged from –8% to 110%. TCP andthe mean dose were reduced up to 21% and 56%, respectively. TCP is observed to decrease as the mean dose decreasesto the prostate. The post-implant tumor dose was generally observed to decrease, compared to the planned dose.A critical uniform dose of 130 Gy was established. Below this dose, TCP begins to fall-off. It was also determined thatpatients with a small prostates were more likely to suffer TCP decrease. Conclusions: The biological effect of post operative prostate growth due to operative trauma in LDR was evaluatedusing the concept. The post-implant dose was lower than the planned dose due to an increase of prostate volumepost-implant. A critical uniform dose of 130 Gy was determined, below which TCP begun to decline.

  13. CryoSat-2 Processing and Model Interpretation of Greenland Ice Sheet Volume Changes

    Science.gov (United States)

    Nilsson, J.; Gardner, A. S.; Sandberg Sorensen, L.

    2015-12-01

    CryoSat-2 was launched in late 2010 tasked with monitoring the changes of the Earth's land and sea ice. It carries a novel radar altimeter allowing the satellite to monitor changes in highly complex terrain, such as smaller ice caps, glaciers and the marginal areas of the ice sheets. Here we present on the development and validation of an independent elevation retrieval processing chain and respective elevation changes based on ESA's L1B data. Overall we find large improvement in both accuracy and precision over Greenland relative to ESA's L2 product when comparing against both airborne data and crossover analysis. The seasonal component and spatial sampling of the surface elevation changes where also compared against ICESat derived changes from 2003-2009. The comparison showed good agreement between the to product on a local scale. However, a global sampling bias was detected in the seasonal signal due to the clustering of CryoSat-2 data in higher elevation areas. The retrieval processing chain presented here does not correct for changes in surface scattering conditions and appears to be insensitive to the 2012 melt event (Nilsson et al., 2015). This in contrast to the elevation changes derived from ESA's L2 elevation product, which where found to be sensitive to the effects of the melt event. The positive elevation bias created by the event introduced a discrepancy between the two products with a magnitude of roughly 90 km3/year. This difference can directly be attributed to the differences in retracking procedure pointing to the importance of the retracking of the radar waveforms for altimetric volume change studies. Greenland 2012 melt event effects on CryoSat-2 radar altimetry./ Nilsson, Johan; Vallelonga, Paul Travis; Simonsen, Sebastian Bjerregaard; Sørensen, Louise Sandberg; Forsberg, René; Dahl-Jensen, Dorthe; Hirabayashi, Motohiro; Goto-Azuma, Kumiko; Hvidberg, Christine S.; Kjær, Helle A.; Satow, Kazuhide.

  14. Automated torso organ segmentation from 3D CT images using structured perceptron and dual decomposition

    Science.gov (United States)

    Nimura, Yukitaka; Hayashi, Yuichiro; Kitasaka, Takayuki; Mori, Kensaku

    2015-03-01

    This paper presents a method for torso organ segmentation from abdominal CT images using structured perceptron and dual decomposition. A lot of methods have been proposed to enable automated extraction of organ regions from volumetric medical images. However, it is necessary to adjust empirical parameters of them to obtain precise organ regions. This paper proposes an organ segmentation method using structured output learning. Our method utilizes a graphical model and binary features which represent the relationship between voxel intensities and organ labels. Also we optimize the weights of the graphical model by structured perceptron and estimate the best organ label for a given image by dynamic programming and dual decomposition. The experimental result revealed that the proposed method can extract organ regions automatically using structured output learning. The error of organ label estimation was 4.4%. The DICE coefficients of left lung, right lung, heart, liver, spleen, pancreas, left kidney, right kidney, and gallbladder were 0.91, 0.95, 0.77, 0.81, 0.74, 0.08, 0.83, 0.84, and 0.03, respectively.

  15. Trunk muscle activation. The effects of torso flexion, moment direction, and moment magnitude.

    Science.gov (United States)

    Lavender, S; Trafimow, J; Andersson, G B; Mayer, R S; Chen, I H

    1994-04-01

    This study was performed to quantify the electromyographic trunk muscle activities in response to variations in moment magnitude and direction while in forward-flexed postures. Recordings were made over eight trunk muscles in 19 subjects who maintained forward-flexed postures of 30 degrees and 60 degrees. In each of the two flexed postures, external moments of 20 Nm and 40 Nm were applied via a chest harness. The moment directions were varied in seven 30 degrees increments to a subject's right side, such that the direction of the applied load ranged from the upper body's anterior midsagittal plane (0 degree) to the posterior midsagittal plane (180 degrees). Statistical analyses yielded significant moment magnitude by moment-direction interaction effects for the EMG output from six of the eight muscles. Trunk flexion by moment-direction interactions were observed in the responses from three muscles. In general, the primary muscle supporting the torso and the applied load was the contralateral (left) erector spinae. The level of electromyographic activity in the anterior muscles was quite low, even with the posterior moment directions.

  16. Mild evaporative cooling applied to the torso provides thermoregulatory benefits during running in the heat.

    Science.gov (United States)

    Filingeri, D; Fournet, D; Hodder, S; Havenith, G

    2015-06-01

    We investigated the effects of mild evaporative cooling applied to the torso, before or during running in the heat. Nine male participants performed three trials: control-no cooling (CTR), pre-exercise cooling (PRE-COOL), and during-exercise cooling (COOL). Trials consisted of 10-min neutral exposure and 50-min heat exposure (30 °C; 44% humidity), during which a 30-min running protocol (70% VO2max ) was performed. An evaporative cooling t-shirt was worn before the heat exposure (PRE-COOL) or 15 min after the exercise was started (COOL). PRE-COOL significantly lowered local skin temperature (Tsk ) (up to -5.3 ± 0.3 °C) (P benefits during exercise in the heat. However, the timing of application was critical in inducing different thermoregulatory responses. These findings provide novel insights on the thermoregulatory role of Tsk during exercise in the heat. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  17. Coupled lattice Boltzmann method for numerical simulations of fully coupled heart and torso bidomain system in electrocardiology

    OpenAIRE

    Corre , Samuel; Belmiloudi , Aziz

    2016-01-01

    International audience; In this work, a modified coupling Lattice Boltzmann Model (LBM) in simulation of cardiac electrophysiology is developed in order to capture the detailed activities of macro- to micro-scale transport processes. The propagation of electrical activity in the human heart through torso is mathematically modeled by bidomain type systems. As transmembrane potential evolves, we take into account domain anisotropical properties using intracellular and extracellular conductivity...

  18. Early-age hydration and volume change of calcium sulfoaluminate cement-based binders

    Science.gov (United States)

    Chaunsali, Piyush

    Shrinkage cracking is a predominant deterioration mechanism in structures with high surface-to-volume ratio. One way to allay shrinkage-induced stresses is to use calcium sulfoaluminate (CSA) cement whose early-age expansion in restrained condition induces compressive stress that can be utilized to counter the tensile stresses due to shrinkage. In addition to enhancing the resistance against shrinkage cracking, CSA cement also has lower carbon footprint than that of Portland cement. This dissertation aims at improving the understanding of early-age volume change of CSA cement-based binders. For the first time, interaction between mineral admixtures (Class F fly ash, Class C fly ash, and silica fume) and OPC-CSA binder was studied. Various physico-chemical factors such as the hydration of ye'elimite (main component in CSA cement), amount of ettringite (the main phase responsible for expansion in CSA cement), supersaturation with respect to ettringite in cement pore solution, total pore volume, and material stiffness were monitored to examine early-age expansion characteristics. This research validated the crystallization stress theory by showing the presence of higher supersaturation level of ettringite, and therefore, higher crystallization stress in CSA cement-based binders. Supersaturation with respect to ettringite was found to increase with CSA dosage and external supply of gypsum. Mineral admixtures (MA) altered the expansion characteristics in OPC-CSA-MA binders with fixed CSA cement. This study reports that fly ash (FA) behaves differently depending on its phase composition. The Class C FA-based binder (OPC-CSA-CFA) ceased expanding beyond two days unlike other OPC-CSA-MA binders. Three factors were found to govern expansion of CSA cement-based binders: 1) volume fraction of ettringite in given pore volume, 2) saturation level of ettringite, and 3) dynamic modulus. Various models were utilized to estimate the macroscopic tensile stress in CSA cement

  19. Cell volume changes regulate slick (Slo2.1), but not slack (Slo2.2) K+ channels.

    Science.gov (United States)

    Tejada, Maria A; Stople, Kathleen; Hammami Bomholtz, Sofia; Meinild, Anne-Kristine; Poulsen, Asser Nyander; Klaerke, Dan A

    2014-01-01

    Slick (Slo2.1) and Slack (Slo2.2) channels belong to the family of high-conductance K+ channels and have been found widely distributed in the CNS. Both channels are activated by Na+ and Cl- and, in addition, Slick channels are regulated by ATP. Therefore, the roles of these channels in regulation of cell excitability as well as ion transport processes, like regulation of cell volume, have been hypothesized. It is the aim of this work to evaluate the sensitivity of Slick and Slack channels to small, fast changes in cell volume and to explore mechanisms, which may explain this type of regulation. For this purpose Slick and Slack channels were co-expressed with aquaporin 1 in Xenopus laevis oocytes and cell volume changes of around 5% were induced by exposure to hypotonic or hypertonic media. Whole-cell currents were measured by two electrode voltage clamp. Our results show that Slick channels are dramatically stimulated (196% of control) by cell swelling and inhibited (57% of control) by a decrease in cell volume. In contrast, Slack channels are totally insensitive to similar cell volume changes. The mechanism underlining the strong volume sensitivity of Slick channels needs to be further explored, however we were able to show that it does not depend on an intact actin cytoskeleton, ATP release or vesicle fusion. In conclusion, Slick channels, in contrast to the similar Slack channels, are the only high-conductance K+ channels strongly sensitive to small changes in cell volume.

  20. Cell volume changes regulate slick (Slo2.1, but not slack (Slo2.2 K+ channels.

    Directory of Open Access Journals (Sweden)

    Maria A Tejada

    Full Text Available Slick (Slo2.1 and Slack (Slo2.2 channels belong to the family of high-conductance K+ channels and have been found widely distributed in the CNS. Both channels are activated by Na+ and Cl- and, in addition, Slick channels are regulated by ATP. Therefore, the roles of these channels in regulation of cell excitability as well as ion transport processes, like regulation of cell volume, have been hypothesized. It is the aim of this work to evaluate the sensitivity of Slick and Slack channels to small, fast changes in cell volume and to explore mechanisms, which may explain this type of regulation. For this purpose Slick and Slack channels were co-expressed with aquaporin 1 in Xenopus laevis oocytes and cell volume changes of around 5% were induced by exposure to hypotonic or hypertonic media. Whole-cell currents were measured by two electrode voltage clamp. Our results show that Slick channels are dramatically stimulated (196% of control by cell swelling and inhibited (57% of control by a decrease in cell volume. In contrast, Slack channels are totally insensitive to similar cell volume changes. The mechanism underlining the strong volume sensitivity of Slick channels needs to be further explored, however we were able to show that it does not depend on an intact actin cytoskeleton, ATP release or vesicle fusion. In conclusion, Slick channels, in contrast to the similar Slack channels, are the only high-conductance K+ channels strongly sensitive to small changes in cell volume.

  1. The localization of focal heart activity via body surface potential measurements: tests in a heterogeneous torso phantom

    International Nuclear Information System (INIS)

    Wetterling, F; Liehr, M; Haueisen, J; Schimpf, P; Liu, H

    2009-01-01

    The non-invasive localization of focal heart activity via body surface potential measurements (BSPM) could greatly benefit the understanding and treatment of arrhythmic heart diseases. However, the in vivo validation of source localization algorithms is rather difficult with currently available measurement techniques. In this study, we used a physical torso phantom composed of different conductive compartments and seven dipoles, which were placed in the anatomical position of the human heart in order to assess the performance of the Recursively Applied and Projected Multiple Signal Classification (RAP-MUSIC) algorithm. Electric potentials were measured on the torso surface for single dipoles with and without further uncorrelated or correlated dipole activity. The localization error averaged 11 ± 5 mm over 22 dipoles, which shows the ability of RAP-MUSIC to distinguish an uncorrelated dipole from surrounding sources activity. For the first time, real computational modelling errors could be included within the validation procedure due to the physically modelled heterogeneities. In conclusion, the introduced heterogeneous torso phantom can be used to validate state-of-the-art algorithms under nearly realistic measurement conditions.

  2. The localization of focal heart activity via body surface potential measurements: tests in a heterogeneous torso phantom

    Science.gov (United States)

    Wetterling, F.; Liehr, M.; Schimpf, P.; Liu, H.; Haueisen, J.

    2009-09-01

    The non-invasive localization of focal heart activity via body surface potential measurements (BSPM) could greatly benefit the understanding and treatment of arrhythmic heart diseases. However, the in vivo validation of source localization algorithms is rather difficult with currently available measurement techniques. In this study, we used a physical torso phantom composed of different conductive compartments and seven dipoles, which were placed in the anatomical position of the human heart in order to assess the performance of the Recursively Applied and Projected Multiple Signal Classification (RAP-MUSIC) algorithm. Electric potentials were measured on the torso surface for single dipoles with and without further uncorrelated or correlated dipole activity. The localization error averaged 11 ± 5 mm over 22 dipoles, which shows the ability of RAP-MUSIC to distinguish an uncorrelated dipole from surrounding sources activity. For the first time, real computational modelling errors could be included within the validation procedure due to the physically modelled heterogeneities. In conclusion, the introduced heterogeneous torso phantom can be used to validate state-of-the-art algorithms under nearly realistic measurement conditions.

  3. Epicardial potentials computed from the body surface potential map using inverse electrocardiography and an individualised torso model improve sensitivity for acute myocardial infarction diagnosis.

    Science.gov (United States)

    Daly, Michael J; Finlay, Dewar D; Guldenring, Daniel; Bond, Raymond R; McCann, Aaron J; Scott, Peter J; Adgey, Jennifer A; Harbinson, Mark T

    2017-12-01

    Epicardial potentials (EPs) derived from the body surface potential map (BSPM) improve acute myocardial infarction (AMI) diagnosis. In this study, we compared EPs derived from the 80-lead BSPM using a standard thoracic volume conductor model (TVCM) with those derived using a patient-specific torso model (PSTM) based on body mass index (BMI). Consecutive patients presenting to both the emergency department and pre-hospital coronary care unit between August 2009 and August 2011 with acute ischaemic-type chest pain at rest were enrolled. At first medical contact, 12-lead electrocardiograms and BSPMs were recorded. The BMI for each patient was calculated. Cardiac troponin T (cTnT) was sampled 12 hours after symptom onset. Patients were excluded from analysis if they had any ECG confounders to interpretation of the ST-segment. A cardiologist assessed the 12-lead ECG for ST-segment elevation myocardial infarction by Minnesota criteria and the BSPM. BSPM ST-elevation (STE) was ⩾0.2 mV in anterior, ⩾0.1 mV in lateral, inferior, right ventricular or high right anterior and ⩾0.05 mV in posterior territories. To derive EPs, the BSPM data were interpolated to yield values at 352 nodes of a Dalhousie torso. Using an inverse solution based on the boundary element method, EPs at 98 cardiac nodes positioned within a standard TVCM were derived. The TVCM was then scaled to produce a PSTM using a model developed from computed tomography in 48 patients of varying BMIs, and EPs were recalculated. EPs >0.3 mV defined STE. A cardiologist blinded to both the 12-lead ECG and BSPM interpreted the EP map. AMI was defined as cTnT ⩾0.1 µg/L. Enrolled were 400 patients (age 62 ± 13 years; 57% male); 80 patients had exclusion criteria. Of the remaining 320 patients, the BMI was an average of 27.8 ± 5.6 kg/m 2 . Of these, 180 (56%) had AMI. Overall, 132 had Minnesota STE on ECG (sensitivity 65%, specificity 89%) and 160 had BSPM STE (sensitivity 81%, specificity 90

  4. Volume changes and electrostriction in the primary photoreactions of various photosynthetic systems: estimation of dielectric coefficient in bacterial reaction centers and of the observed volume changes with the Drude-Nernst equation.

    Science.gov (United States)

    Mauzerall, David; Hou, Jian-Min; Boichenko, Vladimir A

    2002-01-01

    Photoacoustics (PA) allows the determination of enthalpy and volume changes of photoreactions in photosynthetic reaction centers on the 0.1-10 mus time scale. These include the bacterial centers from Rb. sphaeroides, PS I and PS II centers from Synechocystis and in whole cells. In vitro and in vivo PA data on PS I and PS II revealed that both the volume change (-26 A(3)) and reaction enthalpy (-0.4 eV) in PS I are the same as those in the bacterial centers. However the volume change in PS II is small and the enthalpy far larger, -1 eV. Assigning the volume changes to electrostriction allows a coherent explanation of these observations. One can explain the large volume decrease in the bacterial centers with an effective dielectric coefficient of approximately 4. This is a unique approach to this parameter so important in estimation of protein energetics. The value of the volume contraction for PS I can only be explained if the acceptor is the super- cluster (Fe(4)S(4))(Cys(4)) with charge change from -1 to -2. The small volume change in PS II is explained by sub-mus electron transfer from Y(Z) anion to P(680) cation, in which charge is only moved from the Y(Z) anion to the Q(A) with no charge separation or with rapid proton transfer from oxidized Y(Z) to a polar region and thus very little change in electrostriction. At more acid pH equally rapid proton transfer from a neighboring histidine to a polar region may be caused by the electric field of the P(680) cation.

  5. A Decade in Climate Changes and Marine Fisheries: Assessing the Catchment Volume in Peninsular Malaysia

    Science.gov (United States)

    Kamal, A. H. M.

    2016-12-01

    Global climate change variations over the past 30 years have produced numerous impacts in the abundance and production performance of marine fish and fisheries worldwide. The consequences in terms of flooding of low-lying estuarine habitats due to over rainfall, fluctuation of temperature, dilution of water parameters, devastation of feeding and breeding habitats, salinity fluctuations and acidification of waters, high siltation in coastal area, changes in the sea water table and breeding triggers have raised serious concerns for the well-being of marine fisheries and their production. This study shows that the overall total catchment of marine fisheries was decreased 38% in 2009 compared to 1998 while considers the fishing gears and vessels number used in Peninsular Malaysia. Registered vessels number was increased up to 92% in 2009 compared to 1998 which eventually increased the total catchment volume of marine fisheries. In 2009, the catching efforts and performance was far low as per vessels compared to 1998. Analysis of climate change variables shows that temperature was decreased as rainfall was increased within the year from 1998 to 2009. However, it is still early to conclude that whether climate change variables could have unpleasant impacts on fish production in the tropical seas like Malaysia. In spite of that it is predicted that the prolong exists of monsoon and increases of rainfall in this area resulting the stresses and sometimes interfering on the habitat, reproductive cycle and their related ecosystems in this coastal marine environment in tropics.

  6. Volume changes of extremely large and giant intracranial aneurysms after treatment with flow diverter stents

    Energy Technology Data Exchange (ETDEWEB)

    Carneiro, Angelo; Byrne, James V. [ohn Radcliffe Hospital, Oxford Neurovascular and Neuroradiology Research Unit, Nuffield Department of Surgical Sciences, Oxford (United Kingdom); Rane, Neil; Kueker, Wilhelm; Cellerini, Martino; Corkill, Rufus [John Radcliffe Hospital, Department of Neuroradiology, Oxford (United Kingdom)

    2014-01-15

    This study assessed volume changes of unruptured large and giant aneurysms (greatest diameter >20 mm) after treatment with flow diverter (FD) stents. Clinical audit of the cases treated in a single institution, over a 5-year period. Demographic and clinical data were retrospectively collected from the hospital records. Aneurysm volumes were measured by manual outlining at sequential slices using computerised tomography (CT) or magnetic resonance (MR) angiography data. The audit included eight patients (seven females) with eight aneurysms. Four aneurysms involved the cavernous segment of the internal carotid artery (ICA), three the supraclinoid ICA and one the basilar artery. Seven patients presented with signs and symptoms of mass effect and one with seizures. All but one aneurysm was treated with a single FD stent; six aneurysms were also coiled (either before or simultaneously with FD placement). Minimum follow-up time was 6 months (mean 20 months). At follow-up, three aneurysms decreased in size, three were unchanged and two increased. Both aneurysms that increased in size showed persistent endosaccular flow at follow-up MR; in one case, failure was attributed to suboptimal position of the stent; in the other case, it was attributed to persistence of a side branch originating from the aneurysm (similar to the endoleak phenomenon of aortic aneurysms). At follow-up, five aneurysms were completely occluded; none of these increased in volume. Complete occlusion of the aneurysms leads, in most cases, to its shrinkage. In cases of late aneurysm growth or regrowth, consideration should be given to possible endoleak as the cause. (orig.)

  7. The study of dose variation and change of heart volume using 4D-CT in left breast radiation therapy

    International Nuclear Information System (INIS)

    Park, Seon Mi; Cheon, Geum Seong; Heo, Gyeong Hun; Shin, Sung Pil; Kim, Kwang Seok; Kim, Chang Uk; Kim, Hoi Nam

    2013-01-01

    We investigate the results of changed heart volume and heart dose in the left breast cancer patients while considering the movements of respiration. During the months of March and May in 2012, we designated the 10 patients who had tangential irradiation with left breast cancer in the department of radiation Oncology. With acquired images of free breathing pattern through 3D and 4D CT, we had planed enough treatment filed for covered up the whole left breast. It compares the results of the exposed dose and the volume of heart by DVH (Dose Volume histogram). Although total dose was 50.4 Gy (1.8 Gy/28 fraction), reirradiated 9 Gy (1.8 Gy/5 Fraction) with PTV (Planning Target Volume) if necessary. It compares the results of heart volume and heart dose with the free breathing in 3D CT and 4D CT. It represents the maximum difference volume of heart is 40.5%. In addition, it indicated the difference volume of maximum and minimum, average are 8.8% and 27.9%, 37.4% in total absorbed dose of heart. In case of tangential irradiation (opposite beam) in left breast cancer patients, it is necessary to consider the changed heart volume by the respiration of patient and the heartbeat of patient

  8. Improving estimation of glacier volume change: a GLIMS case study of Bering Glacier System, Alaska

    Directory of Open Access Journals (Sweden)

    M. J. Beedle

    2008-04-01

    Full Text Available The Global Land Ice Measurements from Space (GLIMS project has developed tools and methods that can be employed by analysts to create accurate glacier outlines. To illustrate the importance of accurate glacier outlines and the effectiveness of GLIMS standards we conducted a case study on Bering Glacier System (BGS, Alaska. BGS is a complex glacier system aggregated from multiple drainage basins, numerous tributaries, and many accumulation areas. Published measurements of BGS surface area vary from 1740 to 6200 km2, depending on how the boundaries of this system have been defined. Utilizing GLIMS tools and standards we have completed a new outline (3630 km2 and analysis of the area-altitude distribution (hypsometry of BGS using Landsat images from 2000 and 2001 and a US Geological Survey 15-min digital elevation model. We compared this new hypsometry with three different hypsometries to illustrate the errors that result from the widely varying estimates of BGS extent. The use of different BGS hypsometries results in highly variable measures of volume change and net balance (bn. Applying a simple hypsometry-dependent mass-balance model to different hypsometries results in a bn rate range of −1.0 to −3.1 m a−1 water equivalent (W.E., a volume change range of −3.8 to −6.7 km3 a−1 W.E., and a near doubling in contributions to sea level equivalent, 0.011 mm a−1 to 0.019 mm a−1. Current inaccuracies in glacier outlines hinder our ability to correctly quantify glacier change. Understanding of glacier extents can become comprehensive and accurate. Such accuracy is possible with the increasing volume of satellite imagery of glacierized regions, recent advances in tools and standards, and dedication to this important task.

  9. Depth Dose Distribution Study within a Phantom Torso after Irradiation with a Simulated Solar Particle Event at NSRL

    Science.gov (United States)

    Berger, Thomas; Matthiae, Daniel; Koerner, Christine; George, Kerry; Rhone, Jordan; Cucinotta, Francis; Reitz, Guenther

    2010-01-01

    The adequate knowledge of the radiation environment and the doses incurred during a space mission is essential for estimating an astronaut's health risk. The space radiation environment is complex and variable, and exposures inside the spacecraft and the astronaut's body are compounded by the interactions of the primary particles with the atoms of the structural materials and with the body itself Astronauts' radiation exposures are measured by means of personal dosimetry, but there remains substantial uncertainty associated with the computational extrapolation of skin dose to organ dose, which can lead to over- or underestimation of the health risk. Comparisons of models to data showed that the astronaut's Effective dose (E) can be predicted to within about a +10% accuracy using space radiation transport models for galactic cosmic rays (GCR) and trapped radiation behind shielding. However for solar particle event (SPE) with steep energy spectra and for extra-vehicular activities on the surface of the moon where only tissue shielding is present, transport models predict that there are large differences in model assumptions in projecting organ doses. Therefore experimental verification of SPE induced organ doses may be crucial for the design of lunar missions. In the research experiment "Depth dose distribution study within a phantom torso" at the NASA Space Radiation Laboratory (NSRL) at BNL, Brookhaven, USA the large 1972 SPE spectrum was simulated using seven different proton energies from 50 up to 450 MeV. A phantom torso constructed of natural bones and realistic distributions of human tissue equivalent materials, which is comparable to the torso of the MATROSHKA phantom currently on the ISS, was equipped with a comprehensive set of thermoluminescence detectors and human cells. The detectors are applied to assess the depth dose distribution and radiation transport codes (e.g. GEANT4) are used to assess the radiation field and interactions of the radiation field

  10. The anatomy of the aging face: volume loss and changes in 3-dimensional topography.

    Science.gov (United States)

    Coleman, Sydney R; Grover, Rajiv

    2006-01-01

    Facial aging reflects the dynamic, cumulative effects of time on the skin, soft tissues, and deep structural components of the face, and is a complex synergy of skin textural changes and loss of facial volume. Many of the facial manifestations of aging reflect the combined effects of gravity, progressive bone resorption, decreased tissue elasticity, and redistribution of subcutaneous fullness. A convenient method for assessing the morphological effects of aging is to divide the face into the upper third (forehead and brows), middle third (midface and nose), and lower third (chin, jawline, and neck). The midface is an important factor in facial aesthetics because perceptions of facial attractiveness are largely founded on the synergy of the eyes, nose, lips, and cheek bones (central facial triangle). For aesthetic purposes, this area should be considered from a 3-dimensional rather than a 2-dimensional perspective, and restoration of a youthful 3-dimensional facial topography should be regarded as the primary goal in facial rejuvenation. Recent years have seen a significant increase in the number of nonsurgical procedures performed for facial rejuvenation. Patients seeking alternatives to surgical procedures include those who require restoration of lost facial volume, those who wish to enhance normal facial features, and those who want to correct facial asymmetry. Important factors in selecting a nonsurgical treatment option include the advantages of an immediate cosmetic result and a short recovery time.

  11. Impacts of future climate change on urban flood volumes in Hohhot in northern China: benefits of climate change mitigation and adaptations

    Directory of Open Access Journals (Sweden)

    Q. Zhou

    2018-01-01

    Full Text Available As China becomes increasingly urbanised, flooding has become a regular occurrence in its major cities. Assessing the effects of future climate change on urban flood volumes is crucial to informing better management of such disasters given the severity of the devastating impacts of flooding (e.g. the 2016 flooding events across China. Although recent studies have investigated the impacts of future climate change on urban flooding, the effects of both climate change mitigation and adaptation have rarely been accounted for together in a consistent framework. In this study, we assess the benefits of mitigating climate change by reducing greenhouse gas (GHG emissions and locally adapting to climate change by modifying drainage systems to reduce urban flooding under various climate change scenarios through a case study conducted in northern China. The urban drainage model – Storm Water Management Model – was used to simulate urban flood volumes using current and two adapted drainage systems (i.e. pipe enlargement and low-impact development, LID, driven by bias-corrected meteorological forcing from five general circulation models in the Coupled Model Intercomparison Project Phase 5 archive. Results indicate that urban flood volume is projected to increase by 52 % over 2020–2040 compared to the volume in 1971–2000 under the business-as-usual scenario (i.e. Representative Concentration Pathway (RCP 8.5. The magnitudes of urban flood volumes are found to increase nonlinearly with changes in precipitation intensity. On average, the projected flood volume under RCP 2.6 is 13 % less than that under RCP 8.5, demonstrating the benefits of global-scale climate change mitigation efforts in reducing local urban flood volumes. Comparison of reduced flood volumes between climate change mitigation and local adaptation (by improving drainage systems scenarios suggests that local adaptation is more effective than climate change mitigation in reducing

  12. Impacts of future climate change on urban flood volumes in Hohhot in northern China: benefits of climate change mitigation and adaptations

    Science.gov (United States)

    Zhou, Qianqian; Leng, Guoyong; Huang, Maoyi

    2018-01-01

    As China becomes increasingly urbanised, flooding has become a regular occurrence in its major cities. Assessing the effects of future climate change on urban flood volumes is crucial to informing better management of such disasters given the severity of the devastating impacts of flooding (e.g. the 2016 flooding events across China). Although recent studies have investigated the impacts of future climate change on urban flooding, the effects of both climate change mitigation and adaptation have rarely been accounted for together in a consistent framework. In this study, we assess the benefits of mitigating climate change by reducing greenhouse gas (GHG) emissions and locally adapting to climate change by modifying drainage systems to reduce urban flooding under various climate change scenarios through a case study conducted in northern China. The urban drainage model - Storm Water Management Model - was used to simulate urban flood volumes using current and two adapted drainage systems (i.e. pipe enlargement and low-impact development, LID), driven by bias-corrected meteorological forcing from five general circulation models in the Coupled Model Intercomparison Project Phase 5 archive. Results indicate that urban flood volume is projected to increase by 52 % over 2020-2040 compared to the volume in 1971-2000 under the business-as-usual scenario (i.e. Representative Concentration Pathway (RCP) 8.5). The magnitudes of urban flood volumes are found to increase nonlinearly with changes in precipitation intensity. On average, the projected flood volume under RCP 2.6 is 13 % less than that under RCP 8.5, demonstrating the benefits of global-scale climate change mitigation efforts in reducing local urban flood volumes. Comparison of reduced flood volumes between climate change mitigation and local adaptation (by improving drainage systems) scenarios suggests that local adaptation is more effective than climate change mitigation in reducing future flood volumes. This has

  13. Estimation of volume and mass and of changes in volume and mass of selected chat piles in the Picher mining district, Ottawa County, Oklahoma, 2005-10

    Science.gov (United States)

    Smith, S. Jerrod

    2013-01-01

    From the 1890s through the 1970s the Picher mining district in northeastern Ottawa County, Oklahoma, was the site of mining and processing of lead and zinc ore. When mining ceased in about 1979, as much as 165–300 million tons of mine tailings, locally referred to as “chat,” remained in the Picher mining district. Since 1979, some chat piles have been mined for aggregate materials and have decreased in volume and mass. Currently (2013), the land surface in the Picher mining district is covered by thousands of acres of chat, much of which remains on Indian trust land owned by allottees. The Bureau of Indian Affairs manages these allotted lands and oversees the sale and removal of chat from these properties. To help the Bureau of Indian Affairs better manage the sale and removal of chat, the U.S. Geological Survey, in cooperation with the Bureau of Indian Affairs, estimated the 2005 and 2010 volumes and masses of selected chat piles remaining on allotted lands in the Picher mining district. The U.S. Geological Survey also estimated the changes in volume and mass of these chat piles for the period 2005 through 2010. The 2005 and 2010 chat-pile volume and mass estimates were computed for 34 selected chat piles on 16 properties in the study area. All computations of volume and mass were performed on individual chat piles and on groups of chat piles in the same property. The Sooner property had the greatest estimated volume (4.644 million cubic yards) and mass (5.253 ± 0.473 million tons) of chat in 2010. Five of the selected properties (Sooner, Western, Lawyers, Skelton, and St. Joe) contained estimated chat volumes exceeding 1 million cubic yards and estimated chat masses exceeding 1 million tons in 2010. Four of the selected properties (Lucky Bill Humbah, Ta Mee Heh, Bird Dog, and St. Louis No. 6) contained estimated chat volumes of less than 0.1 million cubic yards and estimated chat masses of less than 0.1 million tons in 2010. The total volume of all

  14. A reaction-diffusion model for market fluctuations - A relation between price change and traded volumes

    Science.gov (United States)

    Yuvan, Steven; Bier, Martin

    2018-02-01

    Two decades ago Bak et al. (1997) [3] proposed a reaction-diffusion model to describe market fluctuations. In the model buyers and sellers diffuse from opposite ends of a 1D interval that represents a price range. Trades occur when buyers and sellers meet. We show analytically and numerically that the model well reproduces the square-root relation between traded volumes and price changes that is observed in real-life markets. The result is remarkable as this relation has commonly been explained in terms of more elaborate trader strategies. We furthermore explain why the square-root relation is robust under model modifications and we show how real-life bond market data exhibit the square-root relation.

  15. The role of testosterone and estradiol in brain volume changes across adolescence: a longitudinal structural MRI study.

    Science.gov (United States)

    Herting, Megan M; Gautam, Prapti; Spielberg, Jeffrey M; Kan, Eric; Dahl, Ronald E; Sowell, Elizabeth R

    2014-11-01

    It has been postulated that pubertal hormones may drive some neuroanatomical changes during adolescence, and may do so differently in girls and boys. Here, we use growth curve modeling to directly assess how sex hormones [testosterone (T) and estradiol (E₂)] relate to changes in subcortical brain volumes utilizing a longitudinal design. 126 adolescents (63 girls), ages 10 to 14, were imaged and restudied ∼2 years later. We show, for the first time, that best-fit growth models are distinctly different when using hormones as compared to a physical proxy of pubertal maturation (Tanner Stage) or age, to predict brain development. Like Tanner Stage, T and E₂ predicted white matter and right amygdala growth across adolescence in both sexes, independent of age. Tanner Stage also explained decreases in both gray matter and caudate volumes, whereas E₂ explained only gray matter decreases and T explained only caudate volume decreases. No pubertal measures were related to hippocampus development. Although specificity was seen, sex hormones had strikingly similar relationships with white matter, gray matter, right amygdala, and bilateral caudate volumes, with larger changes in brain volume seen at early pubertal maturation (as indexed by lower hormone levels), followed by less robust, or even reversals in growth, by late puberty. These novel longitudinal findings on the relationship between hormones and brain volume change represent crucial first steps toward understanding which aspects of puberty influence neurodevelopment. Copyright © 2014 Wiley Periodicals, Inc.

  16. The molar hydrodynamic volume changes of factor VIIa due to GlycoPEGylation

    DEFF Research Database (Denmark)

    Plesner, Bitten; Westh, Peter; Hvidt, Søren

    2011-01-01

    The effects of GlycoPEGylation on the molar hydrodynamic volume of recombinant human rFVIIa were investigated using rFVIIa and two GlycoPEGylated recombinant human FVIIa derivatives, a linear 10 kDa PEG and a branched 40 kDa PEG, respectively. Molar hydrodynamic volumes were determined by capillary......, that the molar hydrodynamic volume of the conjugated protein is not just an addition of the molar hydrodynamic volume of the PEG and the protein. The molar hydrodynamic volume of the GlycoPEGylated protein is larger than the volume of its composites. These results suggest that both the linear and the branched...

  17. Change of hepatic volume after selective bile duct ligation: an experimental study in the rabbit

    International Nuclear Information System (INIS)

    Lee, Hye Won; Yoon, Yup; Ko, Young Tae; Choi, Woo Suk; Lim, Joo Won; Oh, Joo Hyeong; Rim, Hyeong Teck; Kim, Youn Wha; Lee, Seok Hwan

    1998-01-01

    To evaluate the role of bile duct obstuction in the development of atrophy of the liver, using an animal model. Seven rabbits were divided into two groups: group 1(n=3D5), in which there was selective bile duct ligation, and group 2(n=3D2), which underwent a sham operation. Each group was evaluated using CT for changes in hepatic volume after selective bile duct ligation or a sham operation. In group I, the diameter of dilated bile duct was measured 2, 4, 8, 12 and 16 weeks after bile duct ligation, while gross and histologic change were evaluated in all cases. In group 1, bile duct dilatation was seen on CT two weeks after selective bile duct ligation, and did not change significantly during follow-up. In four of five cases, CT revealed no evidence of significant atrophy of the involved segment. Pathologic specimens, however, revealed dilatation of the bile duct, periductal fibrosis, infiltration of chronic inflammatory cells, and periportal fibrosis. One of five cases showed segmental liver atrophy after selective bile duct ligation. In addion to the above pathologic findings, there was obstruction of the portal vein by foreign body reaction. In group 2, no evidence of dilated bile duct or liver atrophy was revealed by CT or pathologic specimen after a sham operation. During long-term follow-up of 16 weeks, obstruction of the bile duct did not play a major role in the development of lobar atrophy in the rabbit.=20

  18. Novel diffusion tensor imaging technique reveals developmental streamline volume changes in the corticospinal tract associated with leg motor control.

    Science.gov (United States)

    Kamson, David O; Juhász, Csaba; Chugani, Harry T; Jeong, Jeong-Won

    2015-04-01

    Diffusion tensor imaging (DTI) has expanded our knowledge of corticospinal tract (CST) anatomy and development. However, previous developmental DTI studies assessed the CST as a whole, overlooking potential differences in development of its components related to control of the upper and lower extremities. The present cross-sectional study investigated age-related changes, side and gender differences in streamline volume of the leg- and hand-related segments of the CST in children. DTI data of 31 children (1-14 years; mean age: 6±4 years; 17 girls) with normal conventional MRI were analyzed. Leg- and hand-related CST streamline volumes were quantified separately, using a recently validated novel tractography approach. CST streamline volumes on both sides were compared between genders and correlated with age. Higher absolute streamline volumes were found in the left leg-related CST compared to the right (p=0.001) without a gender effect (p=0.4), whereas no differences were found in the absolute hand-related CST volumes (p>0.4). CST leg-related streamline volumes, normalized to hemispheric white matter volumes, declined with age in the right hemisphere only (R=-.51; p=0.004). Absolute leg-related CST streamline volumes showed similar, but slightly weaker correlations. Hand-related absolute or normalized CST streamline volumes showed no age-related variations on either side. These results suggest differential development of CST segments controlling hand vs. leg movements. Asymmetric volume changes in the lower limb motor pathway may be secondary to gradually strengthening left hemispheric dominance and is consistent with previous data suggesting that footedness is a better predictor of hemispheric lateralization than handedness. Copyright © 2014 The Japanese Society of Child Neurology. Published by Elsevier B.V. All rights reserved.

  19. 640-slice DVCT multi-dimensionally and dynamically presents changes in bladder volume and urine flow rate

    Science.gov (United States)

    Su, Yunshan; Fang, Kewei; Mao, Chongwen; Xiang, Shutian; Wang, Jin; Li, Yingwen

    2018-01-01

    The present study aimed to explore the application of 640-slice dynamic volume computed tomography (DVCT) to excretory cystography and urethrography. A total of 70 healthy subjects were included in the study. Excretory cystography and urethrography using 640-slice DVCT was conducted to continuously record the motions of the bladder and the proximal female and male urethra. The patients' voiding process was divided into early, early to middle, middle, middle to late, and late voiding phases. The subjects were analyzed using DVCT and conventional CT. The cross-sectional areas of various sections of the male and female urethra were evaluated, and the average urine flow rate was calculated. The 640-slice DVCT technique was used to dynamically observe the urine flow rate and changes in bladder volume at all voiding phases. The urine volume detected by 640-slice DVCT exhibited no significant difference compared with the actual volume, and no significant difference compared with that determined using conventional CT. Furthermore, no significant difference in the volume of the bladder at each phase of the voiding process was detected between 640-slice DVCT and conventional CT. The results indicate that 640-slice DVCT can accurately evaluate the status of the male posterior urethra and female urethra. In conclusion, 640-slice DVCT is able to multi-dimensionally and dynamically present changes in bladder volume and urine flow rate, and could obtain similar results to conventional CT in detecting urine volume, as well as the status of the male posterior urethra and female urethra. PMID:29467853

  20. Volume changes at macro- and nano-scale in epoxy resins studied by PALS and PVT experimental techniques

    Energy Technology Data Exchange (ETDEWEB)

    Somoza, A. [IFIMAT-UNCentro, Pinto 399, B7000GHG Tandil (Argentina) and CICPBA, Pinto 399, B7000GHG Tandil (Argentina)]. E-mail: asomoza@exa.unicen.edu.ar; Salgueiro, W. [IFIMAT-UNCentro, Pinto 399, B7000GHG Tandil (Argentina); Goyanes, S. [LPMPyMC, Depto. de Fisica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria, Pabellon I, 1428 Buenos Aires (Argentina); Ramos, J. [Materials and Technology Group, Departamento de Ingenieria Quimica y M. Ambiente, Escuela University Politecnica, Universidad Pais Vasco/Euskal Herriko Unibertsitatea, Pz. Europa 1, 20018 Donostia/San Sebastian (Spain); Mondragon, I. [Materials and Technology Group, Departamento de Ingenieria Quimica y M. Ambiente, Escuela University Politecnica, Universidad Pais Vasco/Euskal Herriko Unibertsitatea, Pz. Europa 1, 20018 Donostia/San Sebastian (Spain)

    2007-02-15

    A systematic study on changes in the volumes at macro- and nano-scale in epoxy systems cured with selected aminic hardeners at different pre-cure temperatures is presented. Free- and macroscopic specific-volumes were measured by PALS and pressure-volume-temperature techniques, respectively. An analysis of the relation existing between macro- and nano-scales of the thermosetting networks developed by the different chemical structures is shown. The result obtained indicates that the structure of the hardeners governs the packing of the molecular chains of the epoxy network.

  1. Changes in the air cell volume of artificially incubated ostrich eggs ...

    African Journals Online (AJOL)

    A total of 2160 images of candled, incubated ostrich eggs were digitized to determine the percentage of egg volume occupied by the air cell at different stages of incubation. The air cell on average occupied 2.5% of the volume of fresh eggs. For eggs that hatched successfully, this volume increased to an average of 24.4% ...

  2. Volume changes of whole brain gray matter in pediatric patients with Tourette syndrome: evidence from voxel-based morphometry

    International Nuclear Information System (INIS)

    Liu Yue; Peng Yun; Gao Peiyi; Nie Binbin; Lu Chuankai; Zhang Liping; Ji Zhiying; Yin Guangheng; Yu Tong; Shan Baoci

    2012-01-01

    Objectives: To identify the related abnormalities of gray matter in pediatric patients with Tourette syndrome (TS) by using the optimized voxel-based morphometry (VBM). Methods: Three dimensional T 1 WI was acquired in 31 TS children (28 boys, 3 girts, mean age 8 years, range 4-15 years) and 50 age- and sex-matched controls on a 1.5 Tesla Philips scanner. Images were pre-processed and analyzed using a version of VBM 2 in SPM 2. The whole brain gray matter volume was compared between the study and control group by using t-test. Multivariate linear regression analysis was used for analyzing the correlation between the change of grey matter volume within each brain region (mm 3 ) and YGTSS score and course of disease of TS patients. Statistical analyses were performed by using SPSS 13.0. Results: Using VBM, significant increases in gray matter volumes in left superior parietal lobule, right cerebellar hemisphere and left parahippocampal gyrus were detected in TS patients, and the volume changes were 4059, 2126 and 84 mm 3 (t=3.93, 3.71, 3.58, P<0.05) respectively. Compared to the control group, decreased grey matter volumes were found in medulla and left pons, and the volume changes were 213 and 117 mm 3 (t=3.53, 3.48, P<0.05)respectively. Tic severity was not correlated with any volume changes of gray matter in brain (P>0.05, a small volume correction, KE ≥ 10 voxel). Tic course was negatively correlated with the gray matter volume of left parahippocampal gyrus (Beta =-0.391, P=0.039). Conclusions: Using VBM technique, the gray matter abnormalities can be revealed in TS patients without obvious lesions on conventional MR imaging. The increasing volume of temporal and parietal lobes and cerebellar may be an adaptive anatomical change in response to experiential demand. The gray matter volume of the parahippocampal gyrus may be used as one potential objective index for evaluating the prognosis of TS. (authors)

  3. [Volume changes to the neck lymph node metastases in head-neck tumors. The evaluation of radiotherapeutic treatment success].

    Science.gov (United States)

    Liszka, G; Thalacker, U; Somogyi, A; Németh, G

    1997-08-01

    This work is engaged with the volume change of neck lymph node metastasis of malignant tumors in the head-neck region during radiotherapy. In 54 patients with head and neck tumors, the volume of neck lymph nodes before and after radiation was measured. The volumetry was done with CT planimetry. The total dose was 66 Gy (2 Gy/d) telecobalt from 2 lateral opponated fields. The time of volume change could be defined with measuring of the half-time and the doubling-time by the help of Schwartz formula. After 10 Gy the volume diminution was about 20% and half-time 24 to 26 days. Afterwards the time of volume diminution picked up speed and finally achieved 60 to 72%. Meanwhile the half-time decreased to the half value. The result was independent of the site of primary tumor, the patient's sex and age. In our opinion the effectivity of radiotherapy can best be judged with defining of the volume change of lymph nodes of the neck.

  4. Herpes zoster chronification to postherpetic neuralgia induces brain activity and grey matter volume change

    Science.gov (United States)

    Cao, Song; Qin, Bangyong; Zhang, Yi; Yuan, Jie; Fu, Bao; Xie, Peng; Song, Ganjun; Li, Ying; Yu, Tian

    2018-01-01

    Objective: Herpes zoster (HZ) can develop into postherpetic neuralgia (PHN), which is a chronic neuropathic pain (NP). Whether the chronification from HZ to PHN induced brain functional or structural change is unknown and no study compared the changes of the same brains of patients who transited from HZ to PHN. We minimized individual differences and observed whether the chronification of HZ to PHN induces functional and pain duration dependent grey matter volume (GMV) change in HZ-PHN patients. Methods: To minimize individual differences induced error, we enrolled 12 patients with a transition from HZ to PHN. The functional and structural changes of their brains between the two states were identified with resting-state functional MRI (rs-fMRI) technique (i.e., the regional homogeneity (ReHo) and fractional aptitude of low-frequency fluctuation (fALFF) method) and the voxel based morphometry (VBM) technology respectively. The correlations between MRI parameters (i.e., ΔReHo, ΔfALFF and ΔVBM) and Δpain duration were analyzed too. Results: Compared with HZ brains, PHN brains exhibited abnormal ReHo, fALFF and VBM values in pain matrix (the frontal lobe, parietal lobe, thalamus, limbic lobe and cerebellum) as well as the occipital lobe and temporal lobe. Nevertheless, the activity of vast area of cerebellum and frontal lobe significantly increased while that of occipital lobe and limbic lobe showed apparent decrease when HZ developed to PHN. In addition, PHN brain showed decreased GMV in the frontal lobe, the parietal lobe and the occipital lobe but increased in the cerebellum and the temporal lobe. Correlation analyses showed that some of the ReHo, fALFF and VBM differential areas (such as the cerebellum posterior lobe, the thalamus extra-nuclear and the middle temporal gyrus) correlated well with Δpain duration. Conclusions: HZ chronification induced functional and structural change in cerebellum, occipital lobe, temporal lobe, parietal lobe and limbic lobe

  5. Effect of temperature on volume change behaviour of statically compacted kaolin clay

    Directory of Open Access Journals (Sweden)

    Ileme Ogechi

    2016-01-01

    Full Text Available Several soils are subjected to high temperature due to the environment where they are located or activities around them. For instance, upper layer of soils in tropical regions, soils around geothermal structures, clay barriers around nuclear waste repository systems. Numerous studies have pointed out that high temperature affects the hydro-mechanical properties of soils. Notwithstanding already existing studies, the influence of temperature on soils is still a challenge, as most of these studies are soil specific and cannot be inferred as the behaviour of all soils. This paper presents an experimental study on the influence of temperature on the volume change behaviour of statically compacted kaolin clay. Compacted samples were tested at varying temperatures using a suction controlled oedometer cell. The influence of temperature on the magnitude of volumetric strain occurring during mechanical and thermal loading was investigated. The study showed that an increase in temperature increased the magnitude of volumetric strain of the soil on loading. Additionally, the results presented in the light of LC curve showed that an increase in temperature resulted in the contraction and a change in the position of the LC curve.

  6. Implication of volume changes in uranium oxides: A density functional study

    International Nuclear Information System (INIS)

    Szpunar, B.; Szpunar, J.A.; Milman, V.; Goldberg, A.

    2013-01-01

    In severe nuclear accident scenarios (in air environments and high temperatures) UO 2 fuel pellets oxidise to produce uranium oxides with higher oxygen content, e.g., U 4 O 9 or U 3 O 8 . As a first step in investigating the microstructural changes following UO 2 oxidation to hexagonal high temperature phase of U 3 O 8 , density functional quantum mechanical calculations of the structure, elastic properties and electronic structure of U 3 O 8 have been performed. The calculated properties of hexagonal phase of U 3 O 8 are compared to those of the orthorhombic pseudo-hexagonal phase which is stable at room temperature. The total energy technique based on the local density approximation plus Hubbard U as implemented in the CASTEP code is used to investigate changes in the lattice constants. The first-principles calculations predict a 35-42% increase in volume per uranium atom as a result of the transformation from UO 2 to U 3 O 8 , in agreement with experimental data. The implications of this prediction on the linear expansion and fragmentation of fuel are discussed. (authors)

  7. An image-based model of brain volume biomarker changes in Huntington's disease.

    Science.gov (United States)

    Wijeratne, Peter A; Young, Alexandra L; Oxtoby, Neil P; Marinescu, Razvan V; Firth, Nicholas C; Johnson, Eileanoir B; Mohan, Amrita; Sampaio, Cristina; Scahill, Rachael I; Tabrizi, Sarah J; Alexander, Daniel C

    2018-05-01

    Determining the sequence in which Huntington's disease biomarkers become abnormal can provide important insights into the disease progression and a quantitative tool for patient stratification. Here, we construct and present a uniquely fine-grained model of temporal progression of Huntington's disease from premanifest through to manifest stages. We employ a probabilistic event-based model to determine the sequence of appearance of atrophy in brain volumes, learned from structural MRI in the Track-HD study, as well as to estimate the uncertainty in the ordering. We use longitudinal and phenotypic data to demonstrate the utility of the patient staging system that the resulting model provides. The model recovers the following order of detectable changes in brain region volumes: putamen, caudate, pallidum, insula white matter, nonventricular cerebrospinal fluid, amygdala, optic chiasm, third ventricle, posterior insula, and basal forebrain. This ordering is mostly preserved even under cross-validation of the uncertainty in the event sequence. Longitudinal analysis performed using 6 years of follow-up data from baseline confirms efficacy of the model, as subjects consistently move to later stages with time, and significant correlations are observed between the estimated stages and nonimaging phenotypic markers. We used a data-driven method to provide new insight into Huntington's disease progression as well as new power to stage and predict conversion. Our results highlight the potential of disease progression models, such as the event-based model, to provide new insight into Huntington's disease progression and to support fine-grained patient stratification for future precision medicine in Huntington's disease.

  8. Changes in Treatment Volume of Hormonally Treated and Untreated Cancerous Prostate and its Impact on Rectal Dose

    International Nuclear Information System (INIS)

    Lilleby, Wolfgang; Dale, Einar; Olsen, Dag R.; Gude, Unn; Fossaa, Sophie D.

    2003-01-01

    Late chronic side effects of the rectum constitute one of the principal limiting factors for curative radiation therapy in patients with prostate cancer. The purpose of the study was to determine the impact of immediate androgen deprivation (IAD) prior to conformal radiotherapy on rectal volume exposed to high doses, as compared with a deferred treatment strategy (DAD). Twenty-five patients (13 in the IAD group and 12 in the DAD group) with bulky tumours of the prostate, T3pN1-2M0 from the prospective EORTC trial 30846 were analysed. Three-dimensional conformal radiation treatment plans (3D CRT) using a 4-field box technique were generated based on the digitized computed tomographic or magnetic resonance findings acquired during the first 9 months after inclusion in the EORTC trial. Dose-volume histograms (DVHs) were calculated for the prostate and rectum. In the DAD group, there was no obvious alteration in the mean size of the prostate or other evaluated structures. In the IAD patients, a statistically significant reduction of approximately 40% of the gross tumour volume (GTV) was reached after a 6 months' course of hormonal treatment (p<0.001). High-dose rectal volume was correlated with the volume changes of the GTV (p<0.001). Mean rectal volume receiving 95% or more of the target dose was significantly reduced by 20%. Our study confirms the effect of downsizing of locally advanced prostate tumours following AD treatment and demonstrates the interdependence of the high-dose rectal volume with the volume changes of the GTV. However, the mean beneficial sparing of rectal volume was outweighed in some patients by considerable inter-patient variations

  9. Subclinical changes in MRI-determined right ventricular volumes and function in subjects with prediabetes and diabetes.

    Science.gov (United States)

    Patscheider, Hannah; Lorbeer, Roberto; Auweter, Sigrid; Schafnitzel, Anina; Bayerl, Christian; Curta, Adrian; Rathmann, Wolfgang; Heier, Margit; Meisinger, Christa; Peters, Annette; Bamberg, Fabian; Hetterich, Holger

    2018-07-01

    The aim of this study was to assess subclinical changes in right ventricular volumes and function in subjects with prediabetes and diabetes and controls without a history of cardiovascular disease. Data from 400 participants in the KORA FF4 study without self-reported cardiovascular disease who underwent 3-T whole-body MRI were obtained. The right ventricle was evaluated using the short axis and a four-chamber view. Diabetes was defined according to WHO criteria. Associations between glucose tolerance and right ventricular parameters were assessed using multivariable adjusted linear regression models. Data from 337 participants were available for analysis. Of these, 43 (13%) had diabetes, 87 (26%) had prediabetes, and 207 (61%) were normoglycaemic controls. There was a stepwise decrease in right ventricular volumes in men with prediabetes and diabetes in comparison with controls, including right ventricular end-diastolic volume (β = -20.4 and β = -25.6, respectively; p ≤ 0.005), right ventricular end-systolic volume (β = -12.3 and β = -12.7, respectively; p ≤ 0.037) and right ventricular stroke volume (β = -8.1 and β = -13.1, respectively, p ≤ 0.016). We did not observe any association between prediabetes or diabetes and right ventricular volumes in women or between prediabetes or diabetes and right ventricular ejection fraction in men and women. This study points towards early subclinical changes in right ventricular volumes in men with diabetes and prediabetes. • MRI was used to detect subclinical changes in right ventricular parameters. • Diabetes mellitus is associated with right ventricular dysfunction. • Impairment of right ventricular volumes seems to occur predominantly in men.

  10. Resistance exercise-induced fluid shifts: change in active muscle size and plasma volume

    Science.gov (United States)

    Ploutz-Snyder, L. L.; Convertino, V. A.; Dudley, G. A.

    1995-01-01

    The purpose of this study was to test the hypothesis that the reduction in plasma volume (PV) induced by resistance exercise reflects fluid loss to the extravascular space and subsequently selective increase in cross-sectional area (CSA) of active but not inactive skeletal muscle. We compared changes in active and inactive muscle CSA and PV after barbell squat exercise. Magnetic resonance imaging (MRI) was used to quantify muscle involvement in exercise and to determine CSA of muscle groups or individual muscles [vasti (VS), adductor (Add), hamstring (Ham), and rectus femoris (RF)]. Muscle involvement in exercise was determined using exercise-induced contrast shift in spin-spin relaxation time (T2)-weighted MR images immediately postexercise. Alterations in muscle size were based on the mean CSA of individual slices. Hematocrit, hemoglobin, and Evans blue dye were used to estimate changes in PV. Muscle CSA and PV data were obtained preexercise and immediately postexercise and 15 and 45 min thereafter. A hierarchy of muscle involvement in exercise was found such that VS > Add > Ham > RF, with the Ham and RF showing essentially no involvement. CSA of the VS and Add muscle groups were increased 10 and 5%, respectively, immediately after exercise in each thigh with no changes in Ham and RF CSA. PV was decreased 22% immediately following exercise. The absolute loss of PV was correlated (r2 = 0.75) with absolute increase in muscle CSA immediately postexercise, supporting the notion that increased muscle size after resistance exercise reflects primarily fluid movement from the vascular space into active but not inactive muscle.

  11. Body mapping of cutaneous wetness perception across the human torso during thermo-neutral and warm environmental exposures.

    Science.gov (United States)

    Filingeri, Davide; Fournet, Damien; Hodder, Simon; Havenith, George

    2014-10-15

    Sensing skin wetness is linked to inputs arising from cutaneous cold-sensitive afferents. As thermosensitivity to cold varies significantly across the torso, we investigated whether similar regional differences in wetness perception exist. We also investigated the regional differences in thermal pleasantness and whether these sensory patterns are influenced by ambient temperature. Sixteen males (20 ± 2 yr) underwent a quantitative sensory test under thermo-neutral [air temperature (Tair) = 22°C; relative humidity (RH) = 50%] and warm conditions (Tair = 33°C; RH = 50%). Twelve regions of the torso were stimulated with a dry thermal probe (25 cm(2)) with a temperature of 15°C below local skin temperature (Tsk). Variations in Tsk, thermal, wetness, and pleasantness sensations were recorded. As a result of the same cold-dry stimulus, the skin-cooling response varied significantly by location (P = 0.003). The lateral chest showed the greatest cooling (-5 ± 0.4°C), whereas the lower back showed the smallest (-1.9 ± 0.4°C). Thermal sensations varied significantly by location and independently from regional variations in skin cooling with colder sensations reported on the lateral abdomen and lower back. Similarly, the frequency of perceived skin wetness was significantly greater on the lateral and lower back as opposed to the medial chest. Overall wetness perception was slightly higher under warm conditions. Significantly more unpleasant sensations were recorded when the lateral abdomen and lateral and lower back were stimulated. We conclude that humans present regional differences in skin wetness perception across the torso, with a pattern similar to the regional differences in thermosensitivity to cold. These findings indicate the presence of a heterogeneous distribution of cold-sensitive thermo-afferent information. Copyright © 2014 the American Physiological Society.

  12. Observation of the hypodermic fatty layer of the human torso by computed tomography method

    International Nuclear Information System (INIS)

    Matsuyama, Yoko; Inokuchi, Seiichiro; Suzuki, Masataka

    1984-01-01

    CT images were taken at 7 different longitudinal levels of the torso, and three different body types, which were defined by the Rohrer Index, were discussed. Differences between the sexes were also discussed. 1) Total cross-sectional area: In males, values showed maximum at 2 levels (mid-point of sternum, xiphoid) among 7 levels; and, for females, 2 maximal values appeared at the mid-point of the sternum level and the level of the pubic symphysis. Values at the umbilicus level were smallest in both sexes. 2) Areas of hypodermic fatty layer: Here, the values for males were maximal at the umbilicus level, next largest were found at the lower abdominal level. For females, however, the maximal values appeared at the pubic symphysis and lower abdominal levels and values for the umbilicus level followed in magnitude. 3) Hypodermic fatty layer area ratios to those of the total cross-sectional area: Values here were largest at the umbilicus level in both sexes. For males, the ratio at the lower abdominal level and at the pubic symphysis level followed in this order: For females, the order of magnitude of values was reversed between those two ratios. The most minimal ratio appeared at the level of the xiphoid in both sexes. A tendency towards higher ratios in females than in males was seen at all 7 levels for bodies of the A-type. This was seen, however, only at levels below the upper abdomen for bodies of the C-type, and at all levels, except the umbilicus and lower abdomen, for bodies of the D-type. 4) Thickness of the hypodermic fatty layer: The maximal values in this layer appeared at point F for the superior border, mid-point and xiphoid of sternum levels. For the upper abdominal level, maximal values appeared at point A, and for the umbilicus level, at point D. They were all found at point C for the lower abdominal level and at point A for the pubic symphysis level. (J.P.N.)

  13. Change of tumor target volume during waiting time for intensity-modulated radiotherapy (IMRT) in nasopharyngeal carcinoma

    International Nuclear Information System (INIS)

    Chen Bo; Yi Junlin; Gao Li; Xu Guozhen; Huang Xiaodong; Zhang Zhong; Luo Jingwei; Li Suyan

    2007-01-01

    Objective: To determine the influence of change in tumor target volume of nasopharyngeal carcinoma (NPC) while waiting for intensity modulated radiation therapy (IMRT). Methods: From March 2005 to December 2005, 31 patients with nasopharyngeal carcinoma received IMRT as the initial treatment at the Cancer Hospital of Chinese Academic of Medical Sciences. The original simulation CT scan was acquired before IMRT planning. A second CT scan was acquired before the start of radiotherapy. Wait- ing time was defined as the duration between CT simulation and start of radiotherapy. CT-CT fusion was used to minimize the error of delineation between the first tumor target volume (GTV) and the second tumor target volume (sGTV). Tumor target volume was calculated by treatment planning system. T test was carried out to analyse the difference between GTV and sGTV. Pearson correlation and multivariate linear regression was used to analyse the influence factor of the change betweent GTV and sGTV. Results: Median waiting time was 18 days (range, 9-27 days). There were significant differences between GTV and sGTV of both primary tumor (P=0.009) and metastatic lymphoma (P=0.005 ). Both Pearson correlation and multivariate linear regression showed that the change of primary tumor target volume had significant correlation with the first tumor target volume but had no significant correlation with the waiting time, sex, age, T stage and N stage (1992 Chinese Fuzhou Staging Classification). Conclusions: Within the range of the waiting time ob- served in our study, large volume primary tumor would have had a significant increase in volume, but whether the therapeutic effect would be influenced or not would need to be proved by study of large number of cases. Patients with large volume tumor should be considered to reduce the influence of waiting time by enlarging gross target volume and clinical targe volume and by neoadjuveant chemotherapy. For avoiding the unnecessary high-dose to normal

  14. Age-related changes in volumes of the ventricles, sulci and periventricular hyperintensity area

    International Nuclear Information System (INIS)

    Yamada, Kenji; Matsuzawa, Taiju; Ono, Shuichi; Kawashima, Ryuta; Matsui, Hiroshige; Yamada, Susumu; Hishinuma, Takashi

    1987-01-01

    Brain atrophy in 47 subjects without neurologic disturbances, ranging in age from 46 to 82 years, was studied using magnetic resonance imaging (MRI). Moreover, the association of the periventricular hyperintensity area (PVH) recognized with MRI, was also investigated. The volume percentages of the brain, the ventricles and sulci to cranial cavity were calculated as indicators of brain atrophy. The brain volume index decreased and the indeces of the ventricles and sulci linearly increased with age, significantly. The volume ratio of the ventricles to sulci significantly increased with increasing age (p < 0.01) and the correlation coefficient was 0.38. This ratio showed negative correlation to the brain volume index. The volume percentage of PVH to the cranial cavity started to increase in the sixties and negatively correlated with the brain volume index. There was positive correlation between the ratio of the ventricles to sulci and the index of PVH. (author)

  15. Theoretical study of the partial molar volume change associated with the pressure-induced structural transition of ubiquitin.

    Science.gov (United States)

    Imai, Takashi; Ohyama, Shusaku; Kovalenko, Andriy; Hirata, Fumio

    2007-09-01

    The partial molar volume (PMV) change associated with the pressure-induced structural transition of ubiquitin is analyzed by the three-dimensional reference interaction site model (3D-RISM) theory of molecular solvation. The theory predicts that the PMV decreases upon the structural transition, which is consistent with the experimental observation. The volume decomposition analysis demonstrates that the PMV reduction is primarily caused by the decrease in the volume of structural voids in the protein, which is partially canceled by the volume expansion due to the hydration effects. It is found from further analysis that the PMV reduction is ascribed substantially to the penetration of water molecules into a specific part of the protein. Based on the thermodynamic relation, this result implies that the water penetration causes the pressure-induced structural transition. It supports the water penetration model of pressure denaturation of proteins proposed earlier.

  16. Effect of structural modifications on the drying kinetics of foods: changes in volume, surface area and product shape

    Directory of Open Access Journals (Sweden)

    Antonio De Michelis

    2013-10-01

    Full Text Available Macro and micro-structural changes take place during food dehydration. Macro-structural changes encompass modifications in shape, area and volume. Studies of such changes are important because dehydration kinetics (essential for calculating industrial dryers may be highly influenced by changes in food shape and dimensions. The overall changes in volume, surface area (“shrinkage” and shape (Heywood factor, with provides a close description of food shape were determined experimentally, and the results were correlated with simple expressions. Hence, although dehydration kinetics can be modeled with simplified overall shrinkage expressions, the possibility of selecting a suitable geometry and predicting the characteristics dimensions will provide higher accuracy. An additional unresolved problem is the lack of a general model that predicts macro-structural changes for various foods and diverse geometries. In this work, based on experimental data of sweet and sour cherries, and rose hip fruits, a simplified general model to predict changes in volume and surface area are proposed. To estimate how the changes in characteristic dimensions affect the kinetic studies, experimental drying curves for the three fruits by means of a diffusional model considered the following variants for the characteristic dimensions: (i The radius of the fresh food, assumed constant; (ii The radius of the partially dehydrated product; (iii The radius predicted by the correlation for structural changes, especially volume, obtained in this work and generalized for the three fruits, and (iv to demonstrate the need to study the macro-structural changes for all dehydrated foods, also be present the case of a restructured food.

  17. Influence of unstable footwear on lower leg muscle activity, volume change and subjective discomfort during prolonged standing.

    Science.gov (United States)

    Karimi, Zanyar; Allahyari, Teimour; Azghani, Mahmood Reza; Khalkhali, Hamidreza

    2016-03-01

    The present study was an attempt to investigate the effect of unstable footwear on lower leg muscle activity, volume change and subjective discomfort during prolonged standing. Ten healthy subjects were recruited to stand for 2 h in three footwear conditions: barefoot, flat-bottomed shoe and unstable shoe. During standing, lower leg discomfort and EMG activity of medial gastrocnemius (MG) and tibialis anterior (TA) muscles were continuously monitored. Changes in lower leg volume over standing time also were measured. Lower leg discomfort rating reduced significantly while subjects standing on unstable shoe compared to the flat-bottomed shoe and barefoot condition. For lower leg volume, less changes also were observed with unstable shoe. The activity level and variation of right MG muscle was greater with unstable shoe compared to the other footwear conditions; however regarding the left MG muscle, significant difference was found between unstable shoe and flat-bottomed shoe only for activity level. Furthermore no significant differences were observed for the activity level and variation of TA muscles (right/left) among all footwear conditions. The findings suggested that prolonged standing with unstable footwear produces changes in lower leg muscles activity and leads to less volume changes. Perceived discomfort also was lower for this type of footwear and this might mean that unstable footwear can be used as ergonomic solution for employees whose work requires prolonged standing. Copyright © 2015 Elsevier Ltd and The Ergonomics Society. All rights reserved.

  18. Metopic synostosis: Measuring intracranial volume change following fronto-orbital advancement using three-dimensional photogrammetry.

    Science.gov (United States)

    Freudlsperger, Christian; Steinmacher, Sahra; Bächli, Heidi; Somlo, Elek; Hoffmann, Jürgen; Engel, Michael

    2015-06-01

    There is still disagreement regarding the intracranial volumes of patients with metopic synostosis compared with healthy patients. This study aimed to compare the intracranial volume of children with metopic synostosis before and after surgery to an age- and sex-matched control cohort using three-dimensional (3D) photogrammetry. Eighteen boys with metopic synostosis were operated on using standardized fronto-orbital advancement. Frontal, posterior and total intracranial volumes were measured exactly 1 day pre-operatively and 10 days post-operatively, using 3D photogrammetry. To establish an age- and sex-matched control group, the 3D photogrammetric data of 634 healthy boys between the ages of 3 and 13 months were analyzed. Mean age at surgery was 9 months (SD 1.7). Prior to surgery, boys with metopic synostosis showed significantly reduced frontal and total intracranial volumes compared with the reference group, but similar posterior volumes. After surgery, frontal and total intracranial volumes did not differ statistically from the control group. As children with metopic synostosis showed significantly smaller frontal and total intracranial volumes compared with an age- and sex-matched control group, corrective surgery should aim to achieve volume expansion. Furthermore, 3D photogrammetry provides a valuable alternative to CT scans in the measurement of intracranial volume in children with metopic synostosis, which significantly reduces the amount of radiation exposure to the growing brain. Copyright © 2015 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.

  19. Changes in circulating blood volume after infusion of hydroxyethyl starch 6% in critically ill patients

    DEFF Research Database (Denmark)

    Christensen, P; Andersson, J; Rasmussen, S E

    2001-01-01

    The cardiovascular response to a volume challenge with hydroxyethyl starch (HES) (200/0.5) 6% depends on the relation between the volume of HES 6% infused and the expansion of the blood volume in critically ill patients. However, only relatively limited data exist on the plasma expanding effect...... of infusion of HES 6% in critically ill patients. The purpose of the study was to evaluate the variation in the expansion of the circulating blood volume (CBV) in critically ill patients after infusion of 500 ml of colloid (HES (200/0.5) 6%) using the carbon monoxide method....

  20. Brain-volume changes in young and middle-aged smokers: a DARTEL-based voxel-based morphometry study.

    Science.gov (United States)

    Peng, Peng; Wang, Zhenchang; Jiang, Tao; Chu, Shuilian; Wang, Shuangkun; Xiao, Dan

    2017-09-01

    Many studies have reported brain volume changes in smokers. However, the volume differences of grey matter (GM) and white matter (WM) in young and middle-aged male smokers with different lifetime tobacco consumption (pack-years) remain uncertain. To examine the brain volume change, especially whether more pack-years smoking would be associated with smaller gray matter and white matter volume in young and middle-aged male smokers. We used a 3T MR scanner and performed Diffeomorphic anatomical registration through exponentiated lie algebra (DARTEL)-based voxel-based morphometry on 53 long-term male smokers (30.72 ± 4.19 years) and 53 male healthy non-smokers (30.83 ± 5.18 years). We separated smokers to light and heavy smokers by pack-years and compared brain volume between different smoker groups and non-smokers. And then we did analysis of covariance (ANCOVA) between smokers and non-smokers by setting pack-years as covariates. Light and heavy smokers all displayed smaller GM and WM volume than non-smokers and more obviously in heavy smokers. The main smaller areas in light and heavy smokers were superior temporal gyrus, insula, middle occipital gyrus, posterior cingulate, precuneus in GM and posterior cingulate, thalamus and midbrain in WM, in addition, we also observed more pack-years smoking was associated with some certain smaller GM and WM volumes by ANCOVA. Young and middle-aged male smokers had many smaller brain areas than non-smokers. Some of these areas' volume had negative correlation with pack-years, while some had not. These may due to different pathophysiological role of smokings. © 2015 John Wiley & Sons Ltd.

  1. Effects of volume change on the unsaturated hydraulic conductivity of Sphagnum moss

    Science.gov (United States)

    Golubev, V.; Whittington, P.

    2018-04-01

    Due to the non-vascular nature of Sphagnum mosses, the capitula (growing surface) of the moss must rely solely on capillary action to receive water from beneath. Moss subsides and swells in accordance with water table levels, an effect called "mire-breathing", which has been thought to be a self-preservation mechanism, although no systematic studies have been done to demonstrate exactly how volume change affects hydrophysical properties of moss. In this study, the unsaturated hydraulic conductivity (Kunsat) and water content of two different species of Sphagnum moss were measured at different compression rates, up to the maximum of 77%. The findings show that the Kunsat increases by up to an order of magnitude (10×) with compression up to a certain bulk density of the moss, after which higher levels of compression result in lowered unsaturated hydraulic conductivity. This was coupled with an increase in soil water retention with increased compression. The increase of the Kunsat with compression suggests that the mire-breathing effect should be considered a self-preservation mechanism to provide sufficient amount of water to growing moss in times of low water availability.

  2. Investigating the pore-water chemistry effects on the volume change behaviour of Boom clay

    Science.gov (United States)

    Deng, Y. F.; Cui, Y. J.; Tang, A. M.; Nguyen, X. P.; Li, X. L.; Van Geet, M.

    The Essen site has been chosen as an alternative site for nuclear waste disposal in Belgium. The soil formation involved at this site is the same as at Mol site: Boom clay. However, owing to its geographical situation closer to the sea, Boom clay at Essen presents a pore water salinity 4-5 times higher than Boom clay at Mol. This study aims at studying the effects of pore water salinity on the hydro-mechanical behaviour of Boom clay. Specific oedometer cells were used allowing “flushing” the pore water in soil specimen by synthetic pore water or distilled water. The synthetic pore water used was prepared with the chemistry as that for the site water: 5.037 g/L for core Ess83 and 5.578 g/L for core Ess96. Mechanical loading was then carried out on the soil specimen after flushing. The results show that water salinity effect on the liquid limit is negligible. The saturation or pore water replacement under the in situ effective stress of 2.4 MPa does not induce significant volume change. For Ess83, hydro-mechanical behaviour was found to be slightly influenced by the water salinity; on the contrary, no obvious effect was identified on the hydro-mechanical behaviour of Ess96. This can be attributed to the higher smectite content in Ess83 than in Ess96.

  3. Volume changes upon heating of aerosol particles from biomass burning using transmission electron microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Adachi, Kouji [Meteorological Research Inst., Tsukuba (Japan). Atmospheric Environment and Applied Meteorology Research Dept.; Sedlacek, Arthur J. [Brookhaven National Lab. (BNL), Upton, NY (United States). Environmental and Climate Sciences; Kleinman, Lawrence [Brookhaven National Lab. (BNL), Upton, NY (United States). Environmental and Climate Sciences; Chand, Duli [Pacific Northwest National Lab. (PNNL), Richland, WA (United States). Atmospheric Sciences and Global Change Division; Hubbe, John M. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States). Atmospheric Sciences and Global Change Division; Buseck, Peter R. [Arizona State Univ., Tempe, AZ (United States). School of Earth and Space Exploration and School of Molecular Sciences

    2017-09-26

    The responses of aerosol particles to heating are important for measurements of their chemical, physical, and optical properties, classification, and determination of origin. However, the thermal behavior of organic aerosol particles is largely unknown. We provide a method to analyze such thermal behavior through heating from room temperature to >600°C by using a heating holder within a transmission electron microscope (TEM). Here we describe in-situ shape and size changes and variations in the compositions of individual particles before and after heating. We use ambient samples from wildland and agricultural biomass fires in North America collected during the 2013 Biomass Burn Observation Project (BBOP). The results indicate that individual tar balls (TB; spherical organic material) from biomass burning retained, on average, up to 30% of their volume when heated to 600°C. Chemical analysis reveals that K and Na remain in the residues, whereas S and O were lost. In contrast to bulk sample measurements of carbonaceous particles using thermal/optical carbon analyzers, our single-particle results imply that many individual organic particles consist of multiple types of organic matter having different thermal stabilities. Beyond TBs, our results suggest that because of their thermal stability some organic particles may not be detectable by using aerosol mass spectrometry or thermal/optical carbon analyzers. This result can lead to an underestimate of the abundance of TBs and other organic particles, and therefore biomass burning may have more influence than currently recognized in regional and global climate models.

  4. Investigations into the free-volume changes within starch/plasticizer/nanoclay systems using Positron Annihilation Lifetime Spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Huihua, E-mail: h.liu@federation.edu.au [School of Health Sciences, Federation University Australia, Ballarat, Vic (Australia); Chaudhary, Deeptangshu, E-mail: deepc@ers.com.au [ERS Environmental Risk Solutions PTY LTD, Perth, WA (Australia); Campbell, Colin, E-mail: colin.campbell@anu.edu.au [ARC Centre of Excellence for Antimatter-Matter Studies (CAMS), Research School of Physics and Engineering, Australian National University, Canberra (Australia); Roberts, Jason, E-mail: jxr107@physics.anu.edu.au [ARC Centre of Excellence for Antimatter-Matter Studies (CAMS), Research School of Physics and Engineering, Australian National University, Canberra (Australia); Buckman, Stephen, E-mail: stephen.buckman@anu.edu.au [ARC Centre of Excellence for Antimatter-Matter Studies (CAMS), Research School of Physics and Engineering, Australian National University, Canberra (Australia); Sullivan, James, E-mail: james.sullivan@anu.edu.au [ARC Centre of Excellence for Antimatter-Matter Studies (CAMS), Research School of Physics and Engineering, Australian National University, Canberra (Australia)

    2014-11-14

    The free-volume of a matrix is a fundamental parameter that relates to its molecular and bulk characteristics, such as crystalline change and glass transition behavior. In starch-based bionanocomposite, we investigated the effect of the addition of montmorillonite nanoclay (MMT) and food plasticizers (glycerol and sorbitol) on changes of molecular pore size (including pore volume and pore distribution) using the Positron Annihilation Lifetime Spectroscopy (PALS) method. The results demonstrated counter-intuitive impact of MMT on the total free-volume where the total free-volume increased within the polymeric matrix. When compared to the pure matrix free-volume, the addition of MMT also resulted in the appearance of a broader distribution of the void sizes. The plasticizers, on the other hand, apparently occupied the void spaces, and therefore decreased the free-volume of the matrix. Further, together with the small angle X-ray scattering (SAXS) analysis, we concluded that this is a result of interplay between the plasticizer-plasticizer interactions and the polymer–plasticizer interactions. For example, in the starch/glycerol/MMT system, the pore radii slightly decrease upon the increasing of glycerol amount (OG210 = O.27 nm and OG220 = 0.26 nm), but the relative weight did increase with the increasing glycerol concentration. However, increasing the sorbitol amount increased the pore size from 0.23 nm(OS210) to 0.28 nm(OS220). Furthermore, the addition MMT in the OS010 system, promote the emergence of a new dateable pore radius(0.90 nm), and the total weight significantly increased from 13.70 (OS010) to 19.5% (OS210). We suggest that the pore variation (size and distribution) due to the MMT and plasticizers are reflected in the polymer glass transition and crystallinity because ultimately, the, total free-volume is a reflection of level of interactions existing within the bulk of these nanocomposites. - Highlights: • PALS is applied to explore the

  5. Free volume changes in mechanically milled PS and PC studied by positron annihilation lifetime spectroscopy (PALS)

    NARCIS (Netherlands)

    Günther-Schade, K.; Castricum, H.L.; Ziegler, H.J.; Bakker, H.; Faupel, F.

    2004-01-01

    The effect of mechanical milling on free volume was studied by means of positron annihilation lifetime spectroscopy (PALS) in polystyrene (PS) as a typical brittle polymer and in polycarbonate (PC) as a tough representative. Long-time milling increases the free volume, while a decrease is observed

  6. Postprandial hepatic volume change: spiral CT evaluation in case of liver cirrhosis

    International Nuclear Information System (INIS)

    Rho, Kwang Suk; Moon, Jang Il; Ko, Myong Kwan; Byun, Joo Nam; Kim, Young Suk; Kim, Young Chol; Oh, Jae Hee

    1999-01-01

    To investigate the usefulness of evaluating liver cirrhosis through the measurement of liver volume. In a control group(20 normal subjects) and 20 cirrhotic patients, variations in liver volume before and after a meal were obtained. A case-control study was conducted between the two groups. In the control group, the range of increased liver volume after the meal was 67-186ml. Mean increased liver volume was 119.3ml, the range of percentage increase was 6-12.4% and the mean percentage increase was 9.89%. In cirrhotic patients, the range of increased liver volume after the meal was 1-20ml. Mean increase liver volume was 6.9ml, the range of percentage increase was 0-1.9% and the mean percentage increase was 0.65%. Compared with the control group, cirrhotic patients showed a much smaller increase in liver volume(p<0.01). Difference in variation of liver volume between a control group and cirrhotic patients before and after a meal can be used for the evaluation of liver cirrhosis

  7. Multicenter retrospective study of noncompressible torso hemorrhage: Anatomic locations of bleeding and comparison of endovascular versus open approach.

    Science.gov (United States)

    Chang, Ronald; Fox, Erin E; Greene, Thomas J; Eastridge, Brian J; Gilani, Ramyar; Chung, Kevin K; DeSantis, Stacia M; DuBose, Joseph J; Tomasek, Jeffrey S; Fortuna, Gerald R; Sams, Valerie G; Todd, S Rob; Podbielski, Jeanette M; Wade, Charles E; Holcomb, John B

    2017-07-01

    Rational development of technology for rapid control of noncompressible torso hemorrhage (NCTH) requires detailed understanding of what is bleeding. Our objectives were to describe the anatomic location of truncal bleeding in patients presenting with NCTH and compare endovascular (ENDO) management versus open (OPEN) management. This is a retrospective study of adult trauma patients with NCTH admitted to four urban Level I trauma centers in the Houston and San Antonio metropolitan areas in 2008 to 2012. Inclusion criteria include named axial torso vessel disruption, Abbreviated Injury Scale chest or abdomen score of 3 or higher with shock (base excess, bleeding locations were 25% chest, 41% abdomen, and 31% pelvis. ENDO was used to treat relatively few types of vascular injuries, whereas OPEN and RT injuries were more diverse. ENDO patients had more blunt trauma (95% vs. 34% vs. 32%); severe injuries (median Injury Severity Score, 34 vs. 27 vs. 21), and increased time to intervention (median, 298 vs. 92 vs. 51 minutes) compared with OPEN and RT. Mortality was 15% versus 20% versus 79%. ENDO was associated with decreased mortality compared to OPEN (relative risk, 0.58; 95% confidence interval, 0.46-0.73). Although ENDO may reduce mortality in NCTH patients, significant group differences limit the generalizability of this finding. Therapeutic, level V.

  8. Fabrication of a tissue-equivalent torso phantom for intercalibration of in-vivo transuranic-nuclide counting facilities

    International Nuclear Information System (INIS)

    Griffith, R.V.; Dean, P.N.; Anderson, A.L.; Fisher, J.C.

    1978-01-01

    A tissue-equivalent human-torso phantom has been constructed for calibration of the counting systems used for in-vivo measurement of transuranic nuclides. The phantom contains a human male rib cage, removable model organs, and includes tissue-equivalent chest plates that can be placed over the torso to simulate people with a wide range of statures. The organs included are lungs, heart, liver, kidneys, spleen, and tracheo-bronchial lymph nodes. Polyurethane with different concentrations of calcium carbonate was used to simulate the linear photon-attenuation properties of various human tissues--lean muscle, adipose-muscle mixtures, and cartilage. Foamed polyurethane with calcium carbonate simulates lung tissue. Transuranic isotopes can be incorporated uniformly in the phantom's lungs and other polyurethane-based organs by dissolution of the nitrate form in acetone with lanthanum nitrate carrier. Organs have now been labelled with highly pure 238 Pu, 239 Pu, and 241 Am for calibration measurements. This phantom is the first of three that will be used in a U.S. Department of Energy program of intercomparisons involving more than ten laboratories. The results of the intercomparison will allow participating laboratories to prepare sets of transmission curves that can be used to predict the performance of their counting systems for a wide range of subject builds and organ depositions. The intercomparison will also provide valuable information on the relative performance of a variety of detector systems and counting techniques

  9. BreathSens: A Continuous On-Bed Respiratory Monitoring System With Torso Localization Using an Unobtrusive Pressure Sensing Array.

    Science.gov (United States)

    Liu, Jason J; Huang, Ming-Chun; Xu, Wenyao; Zhang, Xiaoyi; Stevens, Luke; Alshurafa, Nabil; Sarrafzadeh, Majid

    2015-09-01

    The ability to continuously monitor respiration rates of patients in homecare or in clinics is an important goal. Past research showed that monitoring patient breathing can lower the associated mortality rates for long-term bedridden patients. Nowadays, in-bed sensors consisting of pressure sensitive arrays are unobtrusive and are suitable for deployment in a wide range of settings. Such systems aim to extract respiratory signals from time-series pressure sequences. However, variance of movements, such as unpredictable extremities activities, affect the quality of the extracted respiratory signals. BreathSens, a high-density pressure sensing system made of e-Textile, profiles the underbody pressure distribution and localizes torso area based on the high-resolution pressure images. With a robust bodyparts localization algorithm, respiratory signals extracted from the localized torso area are insensitive to arbitrary extremities movements. In a study of 12 subjects, BreathSens demonstrated its respiratory monitoring capability with variations of sleep postures, locations, and commonly tilted clinical bed conditions.

  10. Predictors of Intrathoracic Injury after Blunt Torso Trauma in Children Presenting to an Emergency Department as Trauma Activations.

    Science.gov (United States)

    McNamara, Caitlin; Mironova, Irina; Lehman, Erik; Olympia, Robert P

    2017-06-01

    Thoracic injuries are a major cause of death associated with blunt trauma in children. Screening for injury with chest x-ray study, compared with chest computed tomography (CT) scan, has been controversial, weighing the benefits of specificity with the detriment of radiation exposure. To identify predictors of thoracic injury in children presenting as trauma activations to a Level I trauma center after blunt torso trauma, and to compare these predictors with those previously reported in the literature. We performed a retrospective chart review of pediatric patients (trauma center between June 2010 and June 2013 as a trauma activation after sustaining a blunt torso trauma and who received diagnostic imaging of the chest as part of their initial evaluation. Data analysis was performed on 166 patients. There were 33 patients (20%) with 45 abnormalities detected on diagnostic imaging of the chest, with the most common abnormalities being lung contusion (36%), pneumothorax (22%), and rib fracture (13%). Statistically significant predictors of abnormal diagnostic imaging of the chest included Glasgow Coma Scale score (GCS) trauma include GCS < 15, hypoxia, syncope/dizziness, cervical spine tenderness, thoraco-lumbar-sacral spine tenderness, and abdominal/pelvic tenderness. Copyright © 2016 Elsevier Inc. All rights reserved.

  11. Longitudinal volume changes of the pituitary gland in patients with schizotypal disorder and first-episode schizophrenia.

    Science.gov (United States)

    Takahashi, Tsutomu; Zhou, Shi-Yu; Nakamura, Kazue; Tanino, Ryoichiro; Furuichi, Atsushi; Kido, Mikio; Kawasaki, Yasuhiro; Noguchi, Kyo; Seto, Hikaru; Kurachi, Masayoshi; Suzuki, Michio

    2011-01-15

    An enlarged volume of the pituitary gland has been reported in the schizophrenia spectrum, possibly reflecting the hypothalamic-pituitary-adrenal (HPA) hyperactivity. However, it remains largely unknown whether the pituitary size longitudinally changes in the course of the spectrum disorders. In the present study, longitudinal magnetic resonance imaging (MRI) data were obtained from 18 patients with first-episode schizophrenia, 13 patients with schizotypal disorder, and 20 healthy controls. The pituitary volume was measured at baseline and follow-up (mean, 2.7 years) scans and was compared across groups. The pituitary volume was larger in the schizophrenia patients than controls at baseline, and both patient groups had significantly larger pituitary volume than controls at follow-up. In a longitudinal comparison, both schizophrenia (3.6%/year) and schizotypal (2.7%/year) patients showed significant pituitary enlargement compared with controls (-1.8%/year). In the schizophrenia patients, greater pituitary enlargement over time was associated with less improvement of delusions and higher scores for thought disorders at the follow-up. These findings suggest that the pituitary gland exhibits ongoing volume changes during the early course of the schizophrenia spectrum as a possible marker of state-related impairments. Copyright © 2010 Elsevier Inc. All rights reserved.

  12. Early changes of parotid density and volume predict modifications at the end of therapy and intensity of acute xerostomia

    International Nuclear Information System (INIS)

    Belli, Maria Luisa; Broggi, Sara; Scalco, Elisa; Rizzo, Giovanna; Sanguineti, Giuseppe; Fiorino, Claudio; Cattaneo, Giovanni Mauro; Dinapoli, Nicola; Valentini, Vincenzo; Ricchetti, Francesco

    2014-01-01

    To quantitatively assess the predictive power of early variations of parotid gland volume and density on final changes at the end of therapy and, possibly, on acute xerostomia during IMRT for head-neck cancer. Data of 92 parotids (46 patients) were available. Kinetics of the changes during treatment were described by the daily rate of density (rΔρ) and volume (rΔvol) variation based on weekly diagnostic kVCT images. Correlation between early and final changes was investigated as well as the correlation with prospective toxicity data (CTCAEv3.0) collected weekly during treatment for 24/46 patients. A higher rΔρ was observed during the first compared to last week of treatment (-0,50 vs -0,05HU, p-value = 0.0001). Based on early variations, a good estimation of the final changes may be obtained (Δρ: AUC = 0.82, p = 0.0001; Δvol: AUC = 0.77, p = 0.0001). Both early rΔρ and rΔvol predict a higher ''mean'' acute xerostomia score (≥ median value, 1.57; p-value = 0.01). Median early density rate changes for patients with mean xerostomia score ≥ / 3 /day for rΔρ and rΔvol respectively. Further studies are necessary to definitively assess the potential of early density/volume changes in identifying more sensitive patients at higher risk of experiencing xerostomia. (orig.) [de

  13. Change of mean platelet volume values in asthmatic children as an inflammatory marker.

    Science.gov (United States)

    Tuncel, T; Uysal, P; Hocaoglu, A B; Erge, D O; Karaman, O; Uzuner, N

    2012-01-01

    Asthma is the most common chronic disease of childhood in industrialised countries. T helper-2 (Th-2) cells, mast cells and eosinophils have a role in inflammation of asthma. Recently it was shown that platelets also play a role in asthma. Mean platelet volume shows platelet size and reflects platelet activation. The aim of this retrospective study is to evaluate levels of mean platelet volume in asthmatic patients during asymptomatic periods and exacerbations compared with healthy controls. The study consisted of 100 asthmatic patients (male/female: 55/45, mean age: 8.2±3.3) and 49 age and sex matched healthy children as a control group. Mean platelet volume values of asthmatic patients during asymptomatic period were 7.7±0.8fL while mean platelet volume values in asthmatics during exacerbation were 7.8±0.9fL. Comparison of mean platelet volume values of asthmatic patients and healthy controls both in acute asthmatic attack and asymptomatic period showed no difference (p>0.05). Comparison of mean platelet volume values at asthmatic attack and asymptomatic period also had no difference (p>0.05). The presence of atopy, infection, eosinophilia, elevated immunoglobulin E, and severity of acute asthmatic attack did not influence mean platelet volume values. The results of our study suggest that mean platelet volume values may not be used as a marker in bronchial asthma, although prospective studies with larger number of patients are needed to evaluate the role of mean platelet volume in asthma. Copyright © 2011 SEICAP. Published by Elsevier Espana. All rights reserved.

  14. A pomegranate-inspired nanoscale design for large-volume-change lithium battery anodes

    Science.gov (United States)

    Liu, Nian; Lu, Zhenda; Zhao, Jie; McDowell, Matthew T.; Lee, Hyun-Wook; Zhao, Wenting; Cui, Yi

    2014-03-01

    Silicon is an attractive material for anodes in energy storage devices, because it has ten times the theoretical capacity of its state-of-the-art carbonaceous counterpart. Silicon anodes can be used both in traditional lithium-ion batteries and in more recent Li-O2 and Li-S batteries as a replacement for the dendrite-forming lithium metal anodes. The main challenges associated with silicon anodes are structural degradation and instability of the solid-electrolyte interphase caused by the large volume change (~300%) during cycling, the occurrence of side reactions with the electrolyte, and the low volumetric capacity when the material size is reduced to a nanometre scale. Here, we propose a hierarchical structured silicon anode that tackles all three of these problems. Our design is inspired by the structure of a pomegranate, where single silicon nanoparticles are encapsulated by a conductive carbon layer that leaves enough room for expansion and contraction following lithiation and delithiation. An ensemble of these hybrid nanoparticles is then encapsulated by a thicker carbon layer in micrometre-size pouches to act as an electrolyte barrier. As a result of this hierarchical arrangement, the solid-electrolyte interphase remains stable and spatially confined, resulting in superior cyclability (97% capacity retention after 1,000 cycles). In addition, the microstructures lower the electrode-electrolyte contact area, resulting in high Coulombic efficiency (99.87%) and volumetric capacity (1,270 mAh cm-3), and the cycling remains stable even when the areal capacity is increased to the level of commercial lithium-ion batteries (3.7 mAh cm-2).

  15. Thermal Volume Changes and Creep in the Callovo-Oxfordian Claystone

    Science.gov (United States)

    Belmokhtar, Malik; Delage, Pierre; Ghabezloo, Siavash; Conil, Nathalie

    2017-09-01

    The Callovo-Oxfordian (COx) claystone is considered as a potential host rock for high-level radioactive waste disposal at great depth in France. Given the exothermic nature of radioactive wastes, a temperature elevation planned to be smaller than 100 °C will affect the host rock around the disposal cells. To gain better understanding of the thermal volumetric response of the COx claystone, a new thermal isotropic compression cell was developed with particular attention devoted to monitoring axial and radial strains. To do so, a high-precision LVDTs system ensuring direct contact between the LVDT stem and the claystone sample through the membrane was developed. A short drainage length (10 mm) was also ensured so as to allow full saturation of the sample under stress conditions close to in situ, and fully drained conditions during compression. High-precision strain monitoring allowed to observe a volumetric creep under stress conditions close to in situ. A drained heating test under constant stress carried out afterwards up to 80 °C exhibited a thermoelastic expansion up to a temperature of 48 °C, followed by thermoplastic contraction at higher temperature. Creep volume changes, that appeared to be enhanced by temperature, were modelled by using a simple Kelvin-Voigt model, so as to estimate the instantaneous response of the COx claystone and to determine its thermal expansion coefficient. The temperature at which the transition between thermal expansion and contraction appeared is close to the maximum burial temperature of the Callovo-Oxfordian claystone, estimated at 50 °C. This is in agreement with what has been already observed on the Opalinus Clay by Monfared et al. (2012) that was interpreted as a thermal hardening phenomenon, showing that the material kept the memory of the highest temperature supported during its geological history.

  16. Assessment of bronchodilator response through changes in lung volumes in chronic airflow obstruction

    Directory of Open Access Journals (Sweden)

    J.B. Figueroa-Casas

    2003-10-01

    Full Text Available Although FEV1 improvement is routinely used to define bronchodilator (BD response, it correlates poorly with clinical effects. Changes in lung volumes (LV have shown better correlation with exercise tolerance and might be more sensitive to detect BD effects. We assessed the additional contribution of measuring LV before and after BD to detect acute improvement in lung function not demonstrated by FEV1, and the influence of the response criteria selected on this contribution. We analyzed 98 spirometries and plethismographies performed pre and post BD in patients with airflow obstruction (FEV1/FVC 10% of baseline (D>5 anD>15% were also analyzed. FEV1 identified as responders 32% of patients. Greater proportions were uncovered by slow vital capacity (51%, p5 anD>15%. Mean change and proportions of responders for each LV varied significantly (pSi bien el aumento del VEF1 es habitualmente utilizado para definir respuesta a broncodilatadores (BD, su correlación con efectos clínicos es pobre. Los cambios en volúmenes pulmonares (VP han demostrado mejor correlación con tolerancia al ejercicio y podrían ser más sensibles para detectar efectos de los BD. Nosotros evaluamos la contribución adicional de medir VP antes y después de BD para detectar mejoría funcional aguda no demostrada por cambios del VEF1, y la influencia del criterio de respuesta seleccionado en esta contribución. Se analizaron 98 espirometrías y pletismografías realizadas pre y post BD en pacientes con obstrucción al flujo aéreo (VEF1/CVF 10% del basal (D>5 y 15% fueron también analizados. El VEF1 identificó como respondedores a 32% de los pacientes. Proporciones mayores fueron identificadas por capacidad vital lenta (51%, p5 y 15%. El cambio promedio y las proporciones de respondedores para cada VP variaron significativamente (p<0.05 según que el cambio fuese expresado como porcentaje del basal o del valor predicho. Una proporción considerable de pacientes con obstrucci

  17. Variations in gastric emptying of liquid elicited by acute blood volume changes in awake rats

    Directory of Open Access Journals (Sweden)

    Gondim F. de-A.A.

    1998-01-01

    Full Text Available We have observed that acute blood volume expansion increases the gastroduodenal resistance to the flow of liquid in anesthetized dogs, while retraction decreases it (Santos et al. (1991 Acta Physiologica Scandinavica, 143: 261-269. This study evaluates the effect of blood volume expansion and retraction on the gastric emptying of liquid in awake rats using a modification of the technique of Scarpignato (1980 (Archives Internationales de Pharmacodynamie et de Therapie, 246: 286-294. Male Wistar rats (180-200 g were fasted for 16 h with water ad libitum and 1.5 ml of the test meal (0.5 mg/ml phenol red solution in 5% glucose was delivered to the stomach immediately after random submission to one of the following protocols: 1 normovolemic control (N = 22, 2 expansion (N = 72 by intravenous infusion (1 ml/min of Ringer-bicarbonate solution, volumes of 1, 2, 3 or 5% body weight, or 3 retraction (N = 22 by controlled bleeding (1.5 ml/100 g. Gastric emptying of liquid was inhibited by 19-51.2% (P<0.05 after blood volume expansion (volumes of 1, 2, 3 or 5% body weight. Blood volume expansion produced a sustained increase in central venous pressure while mean arterial pressure was transiently increased during expansion (P<0.05. Blood volume retraction increased gastric emptying by 28.5-49.9% (P<0.05 and decreased central venous pressure and mean arterial pressure (P<0.05. Infusion of the shed blood 10 min after bleeding reversed the effect of retraction on gastric emptying. These findings suggest that gastric emptying of liquid is subject to modulation by the blood volume.

  18. Age dependent white matter lesions and brain volume changes in healthy volunteers

    DEFF Research Database (Denmark)

    Christiansen, P; Larsson, H B; Thomsen, C

    1994-01-01

    The brain of 142 healthy volunteers aged 21 to 80 years were investigated using MR imaging. The number and size of the white matter hyperintensity lesions (WMHL) in the cerebral hemispheres were determined. Furthermore, the volume of the cerebral hemispheres and of the lateral ventricles was meas......The brain of 142 healthy volunteers aged 21 to 80 years were investigated using MR imaging. The number and size of the white matter hyperintensity lesions (WMHL) in the cerebral hemispheres were determined. Furthermore, the volume of the cerebral hemispheres and of the lateral ventricles...... was measured. An almost linear increase in the number of volunteers with WMHL was seen with aging for males and females. With aging a significant decrease in the volume of the cerebral hemispheres was found for males, and a significant increase in the volume of the lateral ventricles was seen for both males...... and females. Our results suggest that with aging central atrophy increases more (relatively) than cortical atrophy. No correlation was found between the decreasing volume of the cerebral hemispheres and the increasing number and size of WMHL, nor between the increasing volume of the lateral ventricles...

  19. Modulation of cadmium-induced mitochondrial dysfunction and volume changes by temperature in rainbow trout (Oncorhynchus mykiss)

    International Nuclear Information System (INIS)

    Onukwufor, John O.; Kibenge, Fred; Stevens, Don; Kamunde, Collins

    2015-01-01

    Highlights: • Interactions of Cd and temperature exacerbate mitochondrial dysfunction and enhance Cd accumulation. • Cd uptake by mitochondria occurs through the Ca uniporter. • Temperature exacerbates Cd-induced mitochondrial volume changes. • Low concentrations of Cd inhibit mitochondrial swelling. - Abstract: We investigated how temperature modulates cadmium (Cd)-induced mitochondrial bioenergetic disturbances, metal accumulation and volume changes in rainbow trout (Oncorhynchus mykiss). In the first set of experiments, rainbow trout liver mitochondrial function and Cd content were measured in the presence of complex I substrates, malate and glutamate, following exposure to Cd (0–100 μM) at three (5, 13 and 25 °C) temperatures. The second set of experiments assessed the effect of temperature on Cd-induced mitochondrial volume changes, including the underlying mechanisms, at 15 and 25 °C. Although temperature stimulated both state 3 and 4 rates of respiration, the coupling efficiency was reduced at temperature extremes due to greater inhibition of state 3 at low temperature and greater stimulation of state 4 at the high temperature. Cadmium exposure reduced the stimulatory effect of temperature on state 3 respiration but increased that on state 4, consequently exacerbating mitochondrial uncoupling. The interaction of Cd and temperature yielded different responses on thermal sensitivity of state 3 and 4 respiration; the Q 10 values for state 3 respiration increased at low temperature (5–13 °C) while those for state 4 increased at high temperature (13–25 °C). Importantly, the mitochondria accumulated more Cd at high temperature suggesting that the observed greater impairment of oxidative phosphorylation with temperature was due, at least in part, to a higher metal burden. Cadmium-induced mitochondrial volume changes were characterized by an early phase of contraction followed by swelling, with temperature changing the kinetics and intensifying

  20. Modulation of cadmium-induced mitochondrial dysfunction and volume changes by temperature in rainbow trout (Oncorhynchus mykiss)

    Energy Technology Data Exchange (ETDEWEB)

    Onukwufor, John O. [Department of Biomedical Sciences, Atlantic Veterinary College, University of Prince Edward Island, Charlottetown, PE, Canada C1A 4P3 (Canada); Kibenge, Fred [Department of Pathology and Microbiology, Atlantic Veterinary College, University of Prince Edward Island, Charlottetown, PE, Canada C1A 4P3 (Canada); Stevens, Don [Department of Biomedical Sciences, Atlantic Veterinary College, University of Prince Edward Island, Charlottetown, PE, Canada C1A 4P3 (Canada); Kamunde, Collins, E-mail: ckamunde@upei.ca [Department of Biomedical Sciences, Atlantic Veterinary College, University of Prince Edward Island, Charlottetown, PE, Canada C1A 4P3 (Canada)

    2015-01-15

    Highlights: • Interactions of Cd and temperature exacerbate mitochondrial dysfunction and enhance Cd accumulation. • Cd uptake by mitochondria occurs through the Ca uniporter. • Temperature exacerbates Cd-induced mitochondrial volume changes. • Low concentrations of Cd inhibit mitochondrial swelling. - Abstract: We investigated how temperature modulates cadmium (Cd)-induced mitochondrial bioenergetic disturbances, metal accumulation and volume changes in rainbow trout (Oncorhynchus mykiss). In the first set of experiments, rainbow trout liver mitochondrial function and Cd content were measured in the presence of complex I substrates, malate and glutamate, following exposure to Cd (0–100 μM) at three (5, 13 and 25 °C) temperatures. The second set of experiments assessed the effect of temperature on Cd-induced mitochondrial volume changes, including the underlying mechanisms, at 15 and 25 °C. Although temperature stimulated both state 3 and 4 rates of respiration, the coupling efficiency was reduced at temperature extremes due to greater inhibition of state 3 at low temperature and greater stimulation of state 4 at the high temperature. Cadmium exposure reduced the stimulatory effect of temperature on state 3 respiration but increased that on state 4, consequently exacerbating mitochondrial uncoupling. The interaction of Cd and temperature yielded different responses on thermal sensitivity of state 3 and 4 respiration; the Q{sub 10} values for state 3 respiration increased at low temperature (5–13 °C) while those for state 4 increased at high temperature (13–25 °C). Importantly, the mitochondria accumulated more Cd at high temperature suggesting that the observed greater impairment of oxidative phosphorylation with temperature was due, at least in part, to a higher metal burden. Cadmium-induced mitochondrial volume changes were characterized by an early phase of contraction followed by swelling, with temperature changing the kinetics and

  1. Associations between volume changes and spatial dose metrics for the urinary bladder during local versus pelvic irradiation for prostate cancer.

    Science.gov (United States)

    Casares-Magaz, Oscar; Moiseenko, Vitali; Hopper, Austin; Pettersson, Niclas Johan; Thor, Maria; Knopp, Rick; Deasy, Joseph O; Muren, Ludvig Paul; Einck, John

    2017-06-01

    Inter-fractional variation in urinary bladder volumes during the course of radiotherapy (RT) for prostate cancer causes deviations between planned and delivered doses. This study compared planned versus daily cone-beam CT (CBCT)-based spatial bladder dose distributions, for prostate cancer patients receiving local prostate treatment (local treatment) versus prostate including pelvic lymph node irradiation (pelvic treatment). Twenty-seven patients (N = 15 local treatment; N = 12 pelvic treatment) were treated using daily image-guided RT (1.8 Gy@43-45 fx), adhering to a full bladder/empty rectum protocol. For each patient, 9-10 CBCTs were registered to the planning CT, using the clinically applied translations. The urinary bladder was manually segmented on each CBCT, 3 mm inner shells were generated, and semi and quadrant sectors were created using axial/coronal cuts. Planned and delivered DVH metrics were compared across patients and between the two groups of treatment (t-test, p bladder volume variations and the dose-volume histograms (DVH) of the bladder and its sectors were evaluated (Spearman's rank correlation coefficient, r s ). Bladder volumes varied considerably during RT (coefficient of variation: 16-58%). The population-averaged planned and delivered DVH metrics were not significantly different at any dose level. Larger treatment bladder volumes resulted in increased absolute volume of the posterior/inferior bladder sector receiving intermediate-high doses, in both groups. The superior bladder sector received less dose with larger bladder volumes for local treatments (r s  ± SD: -0.47 ± 0.32), but larger doses for pelvic treatments (r s  ± SD: 0.74 ± 0.24). Substantial bladder volume changes during the treatment course occurred even though patients were treated under a full bladder/daily image-guided protocol. Larger bladder volumes resulted in less bladder wall spared at the posterior-inferior sector, regardless the

  2. Estimating changes in lichen mat volume through time and related effects on barren ground caribou (Rangifer tarandus groenlandicus) movement.

    Science.gov (United States)

    Rickbeil, Gregory J M; Hermosilla, Txomin; Coops, Nicholas C; White, Joanne C; Wulder, Michael A

    2017-01-01

    Lichens form a critical portion of barren ground caribou (Rangifer tarandus groenlandicus) diets, especially during winter months. Here, we assess lichen mat volume across five herd ranges in the Northwest Territories and Nunavut, Canada, using newly developed composite Landsat imagery. The lichen volume estimator (LVE) was adapted for use across 700 000 km2 of barren ground caribou habitat annually from 1984-2012. We subsequently assessed how LVE changed temporally throughout the time series for each pixel using Theil-Sen's slopes, and spatially by assessing whether slope values were centered in local clusters of similar values. Additionally, we assessed how LVE estimates resulted in changes in barren ground caribou movement rates using an extensive telemetry data set from 2006-2011. The Ahiak/Beverly herd had the largest overall increase in LVE (median = 0.033), while the more western herds had the least (median slopes below zero in all cases). LVE slope pixels were arranged in significant clusters across the study area, with the Cape Bathurst, Bathurst, and Bluenose East herds having the most significant clusters of negative slopes (more than 20% of vegetated land in each case). The Ahiak/Beverly and Bluenose West had the most significant positive clusters (16.3% and 18.5% of vegetated land respectively). Barren ground caribou displayed complex reactions to changing lichen conditions depending on season; the majority of detected associations with movement data agreed with current understanding of barren ground caribou foraging behavior (the exception was an increase in movement velocity at high lichen volume estimates in Fall). The temporal assessment of LVE identified areas where shifts in ecological conditions may have resulted in changing lichen mat conditions, while assessing the slope estimates for clustering identified zones beyond the pixel scale where forage conditions may be changing. Lichen volume estimates associated with barren ground caribou

  3. Estimating changes in lichen mat volume through time and related effects on barren ground caribou (Rangifer tarandus groenlandicus) movement

    Science.gov (United States)

    Hermosilla, Txomin; Coops, Nicholas C.; White, Joanne C.; Wulder, Michael A.

    2017-01-01

    Lichens form a critical portion of barren ground caribou (Rangifer tarandus groenlandicus) diets, especially during winter months. Here, we assess lichen mat volume across five herd ranges in the Northwest Territories and Nunavut, Canada, using newly developed composite Landsat imagery. The lichen volume estimator (LVE) was adapted for use across 700 000 km2 of barren ground caribou habitat annually from 1984–2012. We subsequently assessed how LVE changed temporally throughout the time series for each pixel using Theil-Sen’s slopes, and spatially by assessing whether slope values were centered in local clusters of similar values. Additionally, we assessed how LVE estimates resulted in changes in barren ground caribou movement rates using an extensive telemetry data set from 2006–2011. The Ahiak/Beverly herd had the largest overall increase in LVE (median = 0.033), while the more western herds had the least (median slopes below zero in all cases). LVE slope pixels were arranged in significant clusters across the study area, with the Cape Bathurst, Bathurst, and Bluenose East herds having the most significant clusters of negative slopes (more than 20% of vegetated land in each case). The Ahiak/Beverly and Bluenose West had the most significant positive clusters (16.3% and 18.5% of vegetated land respectively). Barren ground caribou displayed complex reactions to changing lichen conditions depending on season; the majority of detected associations with movement data agreed with current understanding of barren ground caribou foraging behavior (the exception was an increase in movement velocity at high lichen volume estimates in Fall). The temporal assessment of LVE identified areas where shifts in ecological conditions may have resulted in changing lichen mat conditions, while assessing the slope estimates for clustering identified zones beyond the pixel scale where forage conditions may be changing. Lichen volume estimates associated with barren ground caribou

  4. MACULAR CHOROIDAL VOLUME CHANGES AFTER INTRAVITREAL BEVACIZUMAB FOR EXUDATIVE AGE-RELATED MACULAR DEGENERATION.

    Science.gov (United States)

    Palkovits, Stefan; Seidel, Gerald; Pertl, Laura; Malle, Eva M; Hausberger, Silke; Makk, Johanna; Singer, Christoph; Osterholt, Julia; Herzog, Sereina A; Haas, Anton; Weger, Martin

    2017-12-01

    To evaluate the effect of intravitreal bevacizumab on the macular choroidal volume and the subfoveal choroidal thickness in treatment naïve eyes with exudative age-related macular degeneration. The macular choroidal volume and the subfoveal choroidal thickness were measured using enhanced depth imaging optical coherence tomography. After a screening examination, each patient received 3 monthly intravitreal injections of 1.25 mg bevacizumab. One month after the third injection was a final assessment. Forty-seven patients with a mean age of 80 ± 6.4 years were included. The macular choroidal volume decreased significantly from median 4.1 mm (interquartile range 3.4-5.9) to median 3.9 mm (interquartile range 3.1-5.6) between the baseline and final examination (difference -0.46 mm, 95% confidence interval: -0.57 to 0.35, P macular choroidal volume at baseline and subfoveal choroidal thickness at baseline were not associated with the response to treatment. The macular choroidal volume and the subfoveal choroidal thickness decreased significantly after 3 monthly bevacizumab injections for exudative age-related macular degeneration.

  5. Orthostatic changes in the blood volumes of the lower extremities in practically healthy humans

    Energy Technology Data Exchange (ETDEWEB)

    Frolov, V K; Koshkin, V M; Karalkin, A V [Vtoroj Moskovskij Gosudarstvennyj Meditsinskij Inst. (USSR)

    1979-07-01

    The method and the results of measuring the blood volumes in the lower extremities in the horizontal and vertical position of the body are given. A combination of a single-sensor counter of the whole body and a gamma-chamber with the use of two nondiffuse active radioindicators, erythrocytes labelled with /sup 51/Cr and albumin-sup(99m)Tc in certain sequence, is found to be the most optimal for quantitative evaluation of the regional volumes of the blood. To raise the informativeness of the studies the authors recommend distinguishing ''rapid'' and ''slow'' fractions of the blood volume progressive growth in the crus since the correlation of these fractions reflect the specific features of an individual orthostatic reaction for each examinee.

  6. Changes in liver and spleen volume in various types of compensated liver cirrhosis

    International Nuclear Information System (INIS)

    Hoshino, Hiroshi; Tarao, Kazuo; Ito, Yoshihiko

    1988-01-01

    Liver and spleen volume were measured by computed tomography in 8 healthy voluneteers and in 21 patients of various types of compensated liver cirrhosis. Patients were divided into 3 groups (8 of viral group, 6 of alcoholic group and 6 of combined group) according to the histopathological findings of the liver and also according to the history of blood transfusion, HBs-Ag and alcohol drinking habit. Each volume was calculated by adding together the area measurements obtained from successive transverse abdominal scans. In the liver volume (mean±S.E.) alcoholic group (1381±86cm 3 ) was significantly larger than the healthy volunteers (1027±27cm 3 ) (p 3 ) (p 3 ) (p 3 ) was significantly larger than the healthy volunteers (84±4.7cm 3 ) (p 3 ) was significantly larger than the viral group (302±10um 2 ) (p 2 ) was also significantly larger than viral group (p<0.04). (author)

  7. The molar hydrodynamic volume changes of factor VIIa due to GlycoPEGylation.

    Science.gov (United States)

    Plesner, Bitten; Westh, Peter; Hvidt, Søren; Nielsen, Anders D

    2011-06-01

    The effects of GlycoPEGylation on the molar hydrodynamic volume of recombinant human rFVIIa were investigated using rFVIIa and two GlycoPEGylated recombinant human FVIIa derivatives, a linear 10kDa PEG and a branched 40kDa PEG, respectively. Molar hydrodynamic volumes were determined by capillary viscometry and mass spectrometry. The intrinsic viscosities of rFVIIa, its two GlycoPEGylated compounds, and of linear 8kDa, 10kDa, 20kDa and branched 40kDa PEG polymers were determined. The measured intrinsic viscosity of rFVIIa is 6.0mL/g, while the intrinsic viscosities of 10kDa PEG-rFVIIa and 40kDa PEG-rFVIIa are 29.5mL/g and 79.0mL/g, respectively. The intrinsic viscosities of the linear PEG polymers are 20, 22.6 and 41.4mL/g for 8, 10, and 20kDa, respectively, and 61.1mL/g for the branched 40kDa PEG. From the results of the intrinsic viscosity and MALDI-TOF measurements it is evident, that the molar hydrodynamic volume of the conjugated protein is not just an addition of the molar hydrodynamic volume of the PEG and the protein. The molar hydrodynamic volume of the GlycoPEGylated protein is larger than the volume of its composites. These results suggest that both the linear and the branched PEG are not wrapped around the surface of rFVIIa but are chains that are significantly stretched out when attached to the protein. Copyright © 2011 Elsevier B.V. All rights reserved.

  8. Long-term global and regional brain volume changes following severe traumatic brain injury: A longitudinal study with clinical correlates

    DEFF Research Database (Denmark)

    Sidaros, Annette; Skimminge, Arnold Jesper Møller; Liptrot, Matthew George

    2009-01-01

    with percent brain volume change (%BVC) ranging between − 0.6% and − 9.4% (mean − 4.0%). %BVC correlated significantly with injury severity, functional status at both scans, and with 1-year outcome. Moreover, %BVC improved prediction of long-term functional status over and above what could be predicted using......Traumatic brain injury (TBI) results in neurodegenerative changes that progress for months, perhaps even years post-injury. However, there is little information on the spatial distribution and the clinical significance of this late atrophy. In 24 patients who had sustained severe TBI we acquired 3D...... scan time point using SIENAX. Regional distribution of atrophy was evaluated using tensor-based morphometry (TBM). At the first scan time point, brain parenchymal volume was reduced by mean 8.4% in patients as compared to controls. During the scan interval, patients exhibited continued atrophy...

  9. Changes in hippocampal volume and neuron number co-occur with memory decline in old homing pigeons (Columba livia).

    Science.gov (United States)

    Coppola, Vincent J; Kanyok, Nate; Schreiber, Austin J; Flaim, Mary E; Bingman, Verner P

    2016-05-01

    The mammalian hippocampus is particularly susceptible to age-related structural changes, which have been used to explain, in part, age-related memory decline. These changes are generally characterized by atrophy (e.g., a decrease in volume and number of synaptic contacts). Recent studies have reported age-related spatial memory deficits in older pigeons similar to those seen in older mammals. However, to date, little is known about any co-occurring changes in the aging avian hippocampal formation (HF). In the current study, it was found that the HF of older pigeons was actually larger and contained more neurons than the HF of younger pigeons, a finding that suggests that the pattern of structural changes during aging in the avian HF is different from that seen in the mammalian hippocampus. A working hypothesis for relating the observed structural changes with spatial-cognitive decline is offered. Copyright © 2016 Elsevier Inc. All rights reserved.

  10. Free volume and elastic properties changes in Cu-Zr-Ti-Pd bulk glassy alloy on heating

    International Nuclear Information System (INIS)

    Louzguine-Luzgin, Dmitri V.; Yavari, Alain Reza; Fukuhara, Mikio; Ota, Katsumi; Xie, Guoqiang; Vaughan, Gavin; Inoue, Akihisa

    2007-01-01

    The variation of free volume and elastic properties of the Cu 55 Zr 30 Ti 10 Pd 5 glassy alloy on heating was studied. The structure changes on heating were studied by synchrotron X-ray diffraction, differential scanning and isothermal calorimetries. The studied glassy alloy shows a rather high Poisson's ratio exceeding 0.42 which is maintained after the structure relaxation and primary devitrification. Young's and Shear modules decrease upon primary devitrification while Bulk modulus exhibits a maximum after structural relaxation

  11. A multi-step dealloying method to produce nanoporous gold with no volume change and minimal cracking

    Energy Technology Data Exchange (ETDEWEB)

    Sun Ye [Department of Chemical and Materials Engineering, University of Kentucky, 177 F. Paul Anderson Tower, Lexington, KY 40506 (United States); Balk, T. John [Department of Chemical and Materials Engineering, University of Kentucky, 177 F. Paul Anderson Tower, Lexington, KY 40506 (United States)], E-mail: balk@engr.uky.edu

    2008-05-15

    We report a simple two-step dealloying method for producing bulk nanoporous gold with no volume change and no significant cracking. The galvanostatic dealloying method used here appears superior to potentiostatic methods for fabricating millimeter-scale samples. Care must be taken when imaging the nanoscale, interconnected sponge-like structure with a focused ion beam, as even brief exposure caused immediate and extensive cracking of nanoporous gold, as well as ligament coarsening at the surface00.

  12. Gray-Matter Volume Estimate Score: A Novel Semi-Automatic Method Measuring Early Ischemic Change on CT

    OpenAIRE

    Song, Dongbeom; Lee, Kijeong; Kim, Eun Hye; Kim, Young Dae; Lee, Hye Sun; Kim, Jinkwon; Song, Tae-Jin; Ahn, Sung Soo; Nam, Hyo Suk; Heo, Ji Hoe

    2015-01-01

    Background and Purpose We developed a novel method named Gray-matter Volume Estimate Score (GRAVES), measuring early ischemic changes on Computed Tomography (CT) semi-automatically by computer software. This study aimed to compare GRAVES and Alberta Stroke Program Early CT Score (ASPECTS) with regards to outcome prediction and inter-rater agreement. Methods This was a retrospective cohort study. Among consecutive patients with ischemic stroke in the anterior circulation who received intra-art...

  13. The effect of delayed postoperative irradiation on local control of soft tissue sarcomas of the extremity and torso

    International Nuclear Information System (INIS)

    Schwartz, David L.; Einck, John; Hunt, Karen; Bruckner, James; Conrad, Ernest; Koh, W.-J.; Laramore, George E.

    2002-01-01

    Purpose: The impact of delayed adjuvant radiotherapy in patients treated by surgical resection for peripheral or torso soft tissue sarcoma has not been well characterized. We retrospectively examined this issue in an institutional patient cohort. Methods and Materials: One hundred two adult patients were treated at the University of Washington Medical Center between 1981 and 1998 with postoperative radiotherapy for cure of a newly diagnosed soft tissue sarcoma. Of this group, 58 patients had primary intermediate- or high-grade disease of the extremity or torso (50 extremity/8 torso). Tumor histology was predominantly malignant fibrohistiocytoma, synovial cell sarcoma, and leiomyosarcoma. The group was dichotomized according to time interval from definitive resection to the start of adjuvant radiation. Twenty-six patients had a short delay, defined as <4 months, and 32 patients had a long delay of ≥4 months. Both groups were balanced with regard to site, size, margin status, and tumor depth; however, the long-delay group had a larger proportion of high histologic grade lesions and was treated more frequently with chemotherapy (31/32 [97%] for long-delay patients vs. 14/26 [54%] for short-delay patients). Median follow-up was 49.5 months (range: 7-113 months). Median follow-up for patients still alive was 54 months (range: 9-113 months). Survival outcomes were estimated by the Kaplan-Meier method. Results: Overall local relapse-free survival at 5 years from the time of definitive resection was 74%. On univariate analysis, estimated 5-year local relapse-free survival was significantly improved in the short-delay group (88% vs. 62% for the long-delay group, p = 0.048 by log rank). Overall distant relapse-free survival, disease-free survival, and overall survival at 5 years were 77%, 68%, and 86%, respectively. These survival outcomes were statistically equivalent in both radiation delay groups. There was no evidence to suggest that delaying adjuvant systemic therapy

  14. Evaluation of the Free Volume Theory to Predict Moisture Transport and Quality Changes During Broccoli Drying

    NARCIS (Netherlands)

    Jin, X.; Sman, van der R.G.M.; Boxtel, van A.J.B.

    2011-01-01

    Moisture diffusion in porous broccoli florets and stalks is modeled using the free volume and Maxwell-Eucken theories. These theories are based on the mobility of water and concern the variation of the effective diffusion coefficient for a wide range of temperature and moisture content during

  15. Evaluation of the free volume theory to predict moisture transport and quality changes during broccoli drying

    NARCIS (Netherlands)

    Jin, X.; Sman, van der R.G.M.; Boxtel, van A.J.B.

    2010-01-01

    Abstract: Moisture diffusion in porous broccoli florets and stalks is modeled by using the free volume and Maxwell-Eucken theories. These theories are based on the mobility of water and show the variation of the effective diffusion coefficient for a wide range of temperatures and moisture content of

  16. What causes the hippocampal volume decrease in depression? : Are neurogenesis, glial changes and apoptosis implicated?

    NARCIS (Netherlands)

    Czeh, B.; Lucassen, P.J.

    2007-01-01

    Even though in vivo imaging studies document significant reductions of hippocampal volume in depressed patients, the exact underlying cellular mechanisms are unclear. Since stressful life events are associated with an increased risk of developing depression, preclinical studies in which animals are

  17. Cell volume change through water efflux impacts cell stiffness and stem cell fate

    NARCIS (Netherlands)

    Guo, Ming; Pegoraro, Adrian F.; Mao, Angelo; Zhou, Enhua H.; Arany, Praveen R.; Han, Yulong; Burnette, Dylan T.; Jensen, Mikkel H.; Kasza, Karen E.; Moore, Jeffrey R.; Mackintosh, Frederick C.; Fredberg, Jeffrey J.; Mooney, David J.; Lippincott-Schwartz, Jennifer; Weitz, David A.

    2017-01-01

    Cells alter their mechanical properties in response to their local microenvironment; this plays a role in determining cell function and can even influence stem cell fate. Here, we identify a robust and unified relationship between cell stiffness and cell volume. As a cell spreads on a substrate, its

  18. Quantification of Tumor Volume Changes During Radiotherapy for Non-Small-Cell Lung Cancer

    International Nuclear Information System (INIS)

    Fox, Jana; Ford, Eric; Redmond, Kristin; Zhou, Jessica; Wong, John; Song, Danny Y.

    2009-01-01

    Purpose: Dose escalation for lung cancer is limited by normal tissue toxicity. We evaluated sequential computed tomography (CT) scans to assess the possibility of adaptively reducing treatment volumes by quantifying the tumor volume reduction occurring during a course of radiotherapy (RT). Methods and Materials: A total of 22 patients underwent RT for Stage I-III non-small-cell lung cancer with conventional fractionation; 15 received concurrent chemotherapy. Two repeat CT scans were performed at a nominal dose of 30 Gy and 50 Gy. Respiration-correlated four-dimensional CT scans were used for evaluation of respiratory effects in 17 patients. The gross tumor volume (GTV) was delineated on simulation and all individual phases of the repeat CT scans. Parenchymal tumor was evaluated unless the nodal volume was larger or was the primary. Subsequent image sets were spatially co-registered with the simulation data for evaluation. Results: The median GTV reduction was 24.7% (range, -0.3% to 61.7%; p 100 cm 3 vs. 3 , and hilar and/or mediastinal involvement vs. purely parenchymal or pleural lesions. A tendency toward a greater volume reduction with increasing dose was seen, although this did not reach statistical significance. Conclusion: The results of this study have demonstrated significant alterations in the GTV seen on repeat CT scans during RT. These observations raise the possibility of using an adaptive approach toward RT of non-small-cell lung cancer to minimize the dose to normal structures and more safely increase the dose directed at the target tissues.

  19. Early changes of parotid density and volume predict modifications at the end of therapy and intensity of acute xerostomia.

    Science.gov (United States)

    Belli, Maria Luisa; Scalco, Elisa; Sanguineti, Giuseppe; Fiorino, Claudio; Broggi, Sara; Dinapoli, Nicola; Ricchetti, Francesco; Valentini, Vincenzo; Rizzo, Giovanna; Cattaneo, Giovanni Mauro

    2014-10-01

    To quantitatively assess the predictive power of early variations of parotid gland volume and density on final changes at the end of therapy and, possibly, on acute xerostomia during IMRT for head-neck cancer. Data of 92 parotids (46 patients) were available. Kinetics of the changes during treatment were described by the daily rate of density (rΔρ) and volume (rΔvol) variation based on weekly diagnostic kVCT images. Correlation between early and final changes was investigated as well as the correlation with prospective toxicity data (CTCAEv3.0) collected weekly during treatment for 24/46 patients. A higher rΔρ was observed during the first compared to last week of treatment (-0,50 vs -0,05HU, p-value = 0.0001). Based on early variations, a good estimation of the final changes may be obtained (Δρ: AUC = 0.82, p = 0.0001; Δvol: AUC = 0.77, p = 0.0001). Both early rΔρ and rΔvol predict a higher "mean" acute xerostomia score (≥ median value, 1.57; p-value = 0.01). Median early density rate changes for patients with mean xerostomia score ≥ / xerostomia is well predicted by higher rΔρ and rΔvol in the first two weeks of treatment: best cut-off values were -0.50 HU/day and -380 mm(3)/day for rΔρ and rΔvol respectively. Further studies are necessary to definitively assess the potential of early density/volume changes in identifying more sensitive patients at higher risk of experiencing xerostomia.

  20. Impact of the volume change on the ageing effects in Cu-Al-Ni martensite: experiment and theory.

    Science.gov (United States)

    Kosogor, Anna; Xue, Dezhen; Zhou, Yumei; Ding, Xiangdong; Otsuka, Kazuhiro; L'vov, Victor A; Sun, Jun; Ren, Xiaobing

    2013-08-21

    The time evolution of the physical properties of martensite during martensite ageing is traditionally explained by the symmetry-conforming short-range order (SC-SRO) principle, which requires the spatial configuration of crystal defects to follow the symmetry change of the host lattice. In the present study, we show that the volume change of the host lattice also contributes to the ageing effects in Cu-Al-Ni shape memory alloy besides the symmetry change. To substantiate this statement the gradual increase of the storage modulus with time at constant temperature was measured by dynamic mechanical analysis (DMA) and the experimental results were quantitatively described in the framework of the symmetry-conforming Landau theory of martensitic transformations in a crystal with defects. The comparison of experimental and theoretical results confirmed that the time dependence of the storage modulus is caused by two different physical mechanisms. Evaluations showing that the first mechanism is driven by the spontaneous symmetry change and the second mechanism is caused by the volume change after the martensitic transformation was carried out.

  1. Wood decay by brown-rot fungi : changes in pore structure and cell wall volume

    Science.gov (United States)

    Douglas S. Flournoy; T. Kent Kirk; T.L. Highley

    1991-01-01

    Sweetgum (Liquidambar styraciflua L.) wood blocks were decayed by Postia (= Poria) placenta in soilblock cultures. Decay was terminated at various weight losses, and the pore volumes available to four low molecular weight molecules, (water, 4 Å,; glucose, 8 Å,; maltose, 10 Å; and raffinose, 128,) and three dextrans (Mr 6,000, 38 Å; 11,200, 51 Å; nd 17,500, 61 Å) were...

  2. Prostatic edema in 125I permanent prostate implants: Dynamical dosimetry taking volume changes into account

    International Nuclear Information System (INIS)

    Leclerc, Ghyslain; Lavallee, Marie-Claude; Roy, Rene; Vigneault, Eric; Beaulieu, Luc

    2006-01-01

    The purpose of this study is to determine the impact of edema on the dose delivered to the target volume. An evaluation of the edema characteristics was first made, and then a dynamical dosimetry algorithm was developed and used to compare its results to a standard clinical (static) dosimetry. Source positions and prostate contours extracted from 66 clinical cases on images taken at different points in time (planning, implant day, post-implant evaluation) were used, via the mean interseed distance, to characterize edema [initial increase (Δr 0 ), half-life (τ)]. An algorithm was developed to take into account the edema by summing a time series of dose-volume histograms (DVHs) with a weight based on the fraction of the dose delivered during the time interval considered. The algorithm was then used to evaluate the impact of edema on the dosimetry of permanent implants by comparing its results to those of a standard clinical dosimetry. The volumetric study yielded results as follows: the initial prostate volume increase was found to be 1.58 (ranging from 1.15 to 2.48) and the edema half-life, approximately 30 days (range: 3 to 170 days). The dosimetric differences in D 90 observed between the dynamic dosimetry and the clinical one for a single case were up to 15 Gy and depended on the edema half-life and the initial volume increase. The average edema half-life, 30 days, is about 3 times longer than the previously reported 9 days. Dosimetric differences up to 10% of the prescription dose are observed, which can lead to differences in the quality assertion of an implant. The study of individual patient edema resorption with time might be necessary to extract meaningful clinical correlation or biological parameters in permanent implants

  3. Adapting to climate variability and change in Ontario : volume 4 of the Canada country study : climate impacts and adaptation

    Energy Technology Data Exchange (ETDEWEB)

    Smith, J.; Lavender, B. [Smith and Lavender Envrironmental Consultants, ON (Canada); Auld, H.; Broadhurst, D.; Bullock, T. [Environment Canada, Ottawa, ON (Canada). Ontario Region

    1998-03-01

    An assessment of how climate change will affect Ontario over the next century, including its social, biological and economic environment, is presented. The most significant impacts are expected to result from changes in precipitation patterns, in soil moisture, and in greater intensity and frequency of extreme weather events. Some of the major impacts of changing climate discussed in this volume include: (1) more pollution episodes, (2) increased heat stress, (3) lowering of average water levels of the Great Lakes, (4) changes in the hydrologic cycle which could result in variability of water supply for hydroelectric power production, (5) warming waters of the Great Lakes which could cause fish species to shift northward, (6) cool temperate, moderate temperate and grassland regions could expand northwards as the boreal forest retreats, (7) longer crop growing seasons, (8) decreased snow loads, and (9) reduced ice on the Great Lakes which would increase the length of the shipping season. The general conclusion is that adapting to changing climate will require a knowledge of how climate changes occur and how the changes are likely to affect the environment, society and economy. Changes in other key variables such as technology, personal preferences and social values will also influence the rate of climate change and Ontario`s ability to adapt to it. refs., tabs., figs.

  4. Evidence for a multi-species coccolith volume change over the past two centuries: understanding a potential ocean acidification response

    Directory of Open Access Journals (Sweden)

    P. R. Halloran

    2008-12-01

    Full Text Available Major questions surround the species-specific nature of coccolithophore calcification in response to rising atmospheric CO2 levels. Here we present CaCO3 particle volume distribution data from the coccolith size-fraction of a rapidly accumulating North Atlantic sediment core. Without direct volume measurements on coccoliths produced by individual coccolithophore species, and knowledge of organic, as well as inorganic carbon production, it is not possible to state conclusively the coccolithophore calcification change at this site. However, by analysing the size distribution of CaCO3 particles in the less than 10 μm sediment fraction, we demonstrate a changing particle volume since the late 20th Century consistent with an increase in the mass of coccoliths produced by the larger coccolithophore species, and potentially a decrease in mass of coccoliths produced by the smaller species, present at this location. This finding has significant implications for the realistic representation of an assemblage-wide coccolithophore CO2-calcification response in numerical models.

  5. Hyperosmotically induced volume change and calcium signaling in intervertebral disk cells: the role of the actin cytoskeleton.

    Science.gov (United States)

    Pritchard, Scott; Erickson, Geoffrey R; Guilak, Farshid

    2002-11-01

    Loading of the spine alters the osmotic environment in the intervertebral disk (IVD) as interstitial water is expressed from the tissue. Cells from the three zones of the IVD, the anulus fibrosus (AF), transition zone (TZ), and nucleus pulposus (NP), respond to osmotic stress with altered biosynthesis through a pathway that may involve calcium (Ca(2+)) as a second messenger. We examined the hypothesis that IVD cells respond to hyperosmotic stress by increasing the concentration of intracellular calcium ([Ca(2+)](i)) through a mechanism involving F-actin. In response to hyperosmotic stress, control cells from all zones decreased in volume and cells from the AF and TZ exhibited [Ca(2+)](i) transients, while cells from the NP did not. Extracellular Ca(2+) was necessary to initiate [Ca(2+)](i) transients. Stabilization of F-actin with phalloidin prevented the Ca(2+) response in AF and TZ cells and decreased the rate of volume change in cells from all zones, coupled with an increase in the elastic moduli and apparent viscosity. Conversely, actin breakdown with cytochalasin D facilitated Ca(2+) signaling while decreasing the elastic moduli and apparent viscosity for NP cells. These results suggest that hyperosmotic stress induces volume change in IVD cells and may initiate [Ca(2+)](i) transients through an actin-dependent mechanism.

  6. Ice volume changes (1936–1990–2007 and ground-penetrating radar studies of Ariebreen, Hornsund, Spitsbergen

    Directory of Open Access Journals (Sweden)

    Javier Lapazaran

    2013-08-01

    Full Text Available Ariebreen is a small (0.37 km2-valley glacier located in southern Spitsbergen. Our ground-penetrating radar surveys of the glacier show that it is less than 30 m thick on average, with a maximum thickness of 82 m, and it appears to be entirely cold. By analysing digital terrain models of the ice surface from different dates, we determine the area and volume changes during two periods, 1936–1990 and 1990–2007. The total ice volume of the glacier has decreased by 73% during the entire period 1936–2007, which is equivalent to a mean mass balance rate of −0.61±0.17 m y−1 w.eq. The glacier thinning rate has increased markedly between the first and second periods, from −0.50±0.22 to −0.95±0.17 m y−1 w.eq.

  7. Duration of untreated psychosis/illness and brain volume changes in early psychosis.

    Science.gov (United States)

    Rapp, Charlotte; Canela, Carlos; Studerus, Erich; Walter, Anna; Aston, Jacqueline; Borgwardt, Stefan; Riecher-Rössler, Anita

    2017-09-01

    The time period during which patients manifest psychotic or unspecific symptoms prior to treatment (duration of untreated psychosis, DUP, and the duration of untreated illness, DUI) has been found to be moderately associated with poor clinical and social outcome. Equivocal evidence exists of an association between DUP/DUI and structural brain abnormalities, such as reduced hippocampus volume (HV), pituitary volume (PV) and grey matter volume (GMV). Thus, the goal of the present work was to examine if DUP and DUI are associated with abnormalities in HV, PV and GMV. Using a region of interest (ROI) based approach, we present data of 39 patients from the Basel FePsy (Früherkennung von Psychosen, early detection of psychosis) study for which information about DUP, DUI and HV, PV and GMV data could be obtained. Twenty-three of them were first episode psychosis (FEP) and 16 at-risk mental state (ARMS) patients who later made the transition to frank psychosis. In unadjusted analyses, we found a significant positive correlation between DUP and PV in FEP patients. However, when adjusted for covariates, we found no significant correlation between DUP or DUI and HV, PV or GMV anymore. There only was a trend for decreasing GMV with increasing DUI in FEP. Our results do not comprehensively support the hypothesis of a "toxic" effect of the pathogenic mechanism underlying untreated psychosis on brain structure. If there is any effect, it might rather occur very early in the disease process, during which patients experience only unspecific symptoms. Copyright © 2017. Published by Elsevier B.V.

  8. Damage saturation effects on volume and resistivity changes induced by fission-fragment irradiation of copper

    International Nuclear Information System (INIS)

    Birtcher, R.C.; Blewitt, T.H.

    1981-01-01

    Damage production and saturation has been monitored in copper by simultaneous electrical resistivity- and length-change measurements. Damage was introduced by 235 U fission fragments at either 7 or 85 K. At both temperatures, the resistivity and length changes were linearly related to each other for resistivity changes less than 80% saturation resistivity. The linear relationship was the same for both irradiation temperatures and was the same as that observed previously for 10 B fission fragment irrations at 4 K. These results are interpreted to show that the resistivity change per defect is unaffected by irradiation under conditions which lead to interstitial clustering. (orig.)

  9. The effect of androgen deprivation on the early changes in prostate volume following transperineal ultrasound guided interstitial therapy for localized carcinoma of the prostate

    Energy Technology Data Exchange (ETDEWEB)

    Whittington, Richard; Broderick, Gregory A; Arger, Peter; Malkowicz, S Bruce; Epperson, Robert D; Arjomandy, Bijan; Kassaee, Alireza

    1999-07-15

    Purpose: To determine the change in volume of the prostate as a result of neoadjuvant androgen deprivation prior to prostate implant and in the early postimplant period following transperineal ultrasound guided palladium-103 brachytherapy for early-stage prostate cancer. Methods and Materials: Sixty-nine men received 3 to 6 months of androgen deprivation therapy followed by treatment planning ultrasound followed 4 to 8 weeks later by palladium-103 implant of the prostate. All patients had clinical and radiographic stage T1c-T2b adenocarcinoma of the prostate. A second ultrasound study was carried out 11 to 13 days following the implant to determine the change in volume of the prostate as a result of the implant. The prehormonal and preimplant volumes were compared to the postimplant volume to determine the effect of hormones and brachytherapy on prostate volume. Results: The median decrease in prostate volume as a result of androgen deprivation was 33% among the 54 patients with prostate volume determinations prior to hormonal therapy. The reduction in volume was greatest in the quartile of men with the largest initial gland volume (59%) and least in the quartile of men with smallest glands (10%). The median reduction in prostate volume between the treatment planning ultrasound and the follow-up study after implant was 3%, but 23 (33%) patients had an increase in prostate volume, including 16 (23%) who had an increase in volume >20%; 11 of these patients (16%) had an increase in volume >30%. The time course of development and resolution of this edema is not known. The severity of the edema was not related to initial or preimplant prostate volume or duration of hormonal therapy. Conclusions: Prostate edema may significantly affect the dose delivered to the prostate following transperineal ultrasound guided brachytherapy. The effect on the actual delivered dose will be greater when shorter lived isotopes are used. It remains to be observed whether this edema will

  10. Pulmonary Edema and Plasma Volume Changes in Dysbarism. M.S. Thesis - Texas Univ.

    Science.gov (United States)

    Joki, J. A.

    1972-01-01

    Two groups of anesthetized, fasted pigs were utilized. One group of 13 animals (8.5 to 16.6 kilograms) was exposed to a high-pressure environment, and the other group of eight animals (6.9 to 20.0 kilograms) constituted the control group. The experimental group was subjected to an atmosphere of 90 percent nitrogen and 10 percent oxygen at a pressure of 50 psig for 30 minutes and then decompressed at a rate 10 psi/min. Plasma volumes, using both iodine-125-tagged-albumin and chromium-51-tagged-cell dilution techniques, were measured before, immediately after, and at 30 and 60 minutes after decompression. Aortic and right-ventricular systolic pressures were also recorded. At 60 minutes after decompression, blood samples were taken, the animals were sacrificed, and the water content of the lungs, kidneys, livers, and spleens was estimated by measuring tissue wet weight and dry weight. Protein extravasation and tissue blood volumes were determined by measuring the iodine-125-tagged-albumin and chromium-51-tagged-cell spaces in homo-genates of the organs under investigation.

  11. Tumor Volume Changes Assessed by Three-Dimensional Magnetic Resonance Volumetry in Rectal Cancer Patients After Preoperative Chemoradiation: The Impact of the Volume Reduction Ratio on the Prediction of Pathologic Complete Response

    International Nuclear Information System (INIS)

    Kang, Jeong Hyun; Kim, Young Chul; Kim, Hyunki; Kim, Young Wan; Hur, Hyuk; Kim, Jin Soo; Min, Byung Soh; Kim, Hogeun; Lim, Joon Seok; Seong, Jinsil; Keum, Ki Chang; Kim, Nam Kyu

    2010-01-01

    Purpose: The aim of this study was to determine the correlation between tumor volume changes assessed by three-dimensional (3D) magnetic resonance (MR) volumetry and the histopathologic tumor response in rectal cancer patients undergoing preoperative chemoradiation therapy (CRT). Methods and Materials: A total of 84 patients who underwent preoperative CRT followed by radical surgery were prospectively enrolled in the study. The post-treatment tumor volume and tumor volume reduction ratio (% decrease ratio), as shown by 3D MR volumetry, were compared with the histopathologic response, as shown by T and N downstaging and the tumor regression grade (TRG). Results: There were no significant differences in the post-treatment tumor volume and the volume reduction ratio shown by 3D MR volumetry with respect to T and N downstaging and the tumor regression grade. In a multivariate analysis, the tumor volume reduction ratio was not significantly associated with T and N downstaging. The volume reduction ratio (>75%, p = 0.01) and the pretreatment carcinoembryonic antigen level (≤3 ng/ml, p = 0.01), but not the post-treatment volume shown by 3D MR (≤ 5ml), were, however, significantly associated with an increased pathologic complete response rate. Conclusion: More than 75% of the tumor volume reduction ratios were significantly associated with a high pathologic complete response rate. Therefore, limited treatment options such as local excision or simple observation might be considered after preoperative CRT in this patient population.

  12. Weekly Volume and Dosimetric Changes During Chemoradiotherapy With Intensity-Modulated Radiation Therapy for Head and Neck Cancer: A Prospective Observational Study

    Energy Technology Data Exchange (ETDEWEB)

    Bhide, Shreerang A [Institute of Cancer Research, 237 Fulham Road, London SW6 6JB (United Kingdom); Head and Neck Unit, Royal Marsden NHS Foundation Trust Hospital, London SW3 6JJ (United Kingdom); Davies, Mark; Burke, Kevin; McNair, Helen A; Hansen, Vibeke [Department of Radiation Oncology, Royal Marsden NHS Foundation Trust Hospital, London and Sutton (United Kingdom); Barbachano, Y [Department of Statistics, Royal Marsden NHS Foundation Trust Hospital, London and Sutton (United Kingdom); El-Hariry, I A [Head and Neck Unit, Royal Marsden NHS Foundation Trust Hospital, London SW3 6JJ (United Kingdom); Newbold, Kate [Department of Radiation Oncology, Royal Marsden NHS Foundation Trust Hospital, London and Sutton (United Kingdom); Harrington, Kevin J [Institute of Cancer Research, 237 Fulham Road, London SW6 6JB (United Kingdom); Head and Neck Unit, Royal Marsden NHS Foundation Trust Hospital, London SW3 6JJ (United Kingdom); Nutting, Christopher M., E-mail: chris.nutting@rmh.nhs.u [Head and Neck Unit, Royal Marsden NHS Foundation Trust Hospital, London SW3 6JJ (United Kingdom)

    2010-04-15

    Purpose: The aim of this study was to investigate prospectively the weekly volume changes in the target volumes and organs at risk and the resulting dosimetric changes during induction chemotherapy followed by chemoradiotherapy with intensity-modulated radiation therapy (C-IMRT) for head-and-neck cancer patients. Methods and Materials: Patients receiving C-IMRT for head-and-neck cancer had repeat CT scans at weeks 2, 3, 4, and 5 during radiotherapy. The volume changes of clinical target volume 1 (CTV1) and CTV2 and the resulting dosimetric changes to planning target volume 1 (PTV1) and PTV2 and the organs at risk were measured. Results: The most significant volume differences were seen at week 2 for CTV1 and CTV2. The reductions in the volumes of CTV1 and CTV2 at week 2 were 3.2% and 10%, respectively (p = 0.003 and p < 0.001). The volume changes resulted in a significant reduction in the minimum dose to PTV1 and PTV2 (2 Gy, p = 0.002, and 3.9 Gy, p = 0.03, respectively) and an increased dose range across PTV1 and PTV2 (2.5 Gy, p < 0.001, and 5.1 Gy, p = 0.008, respectively). There was a 15% reduction in the parotid volumes by week 2 (p < 0.001) and 31% by week 4 (p < 0.001). There was a statistically significant increase in the mean dose to the ipsilateral parotid only at week 4 (2.7 Gy, p = 0.006). The parotid glands shifted medially by an average of 2.3 mm (p < 0.001) by week 4. Conclusion: The most significant volumetric changes and dosimetric alterations in the tumor volumes and organs at risk during a course of C-IMRT occur by week 2 of radiotherapy. Further adaptive radiotherapy with replanning, if appropriate, is recommended.

  13. Quantification of surface water volume changes in the Mackenzie Delta using satellite multi-mission data

    Science.gov (United States)

    Normandin, Cassandra; Frappart, Frédéric; Lubac, Bertrand; Bélanger, Simon; Marieu, Vincent; Blarel, Fabien; Robinet, Arthur; Guiastrennec-Faugas, Léa

    2018-02-01

    Quantification of surface water storage in extensive floodplains and their dynamics are crucial for a better understanding of global hydrological and biogeochemical cycles. In this study, we present estimates of both surface water extent and storage combining multi-mission remotely sensed observations and their temporal evolution over more than 15 years in the Mackenzie Delta. The Mackenzie Delta is located in the northwest of Canada and is the second largest delta in the Arctic Ocean. The delta is frozen from October to May and the recurrent ice break-up provokes an increase in the river's flows. Thus, this phenomenon causes intensive floods along the delta every year, with dramatic environmental impacts. In this study, the dynamics of surface water extent and volume are analysed from 2000 to 2015 by combining multi-satellite information from MODIS multispectral images at 500 m spatial resolution and river stages derived from ERS-2 (1995-2003), ENVISAT (2002-2010) and SARAL (since 2013) altimetry data. The surface water extent (permanent water and flooded area) peaked in June with an area of 9600 km2 (±200 km2) on average, representing approximately 70 % of the delta's total surface. Altimetry-based water levels exhibit annual amplitudes ranging from 4 m in the downstream part to more than 10 m in the upstream part of the Mackenzie Delta. A high overall correlation between the satellite-derived and in situ water heights (R > 0.84) is found for the three altimetry missions. Finally, using altimetry-based water levels and MODIS-derived surface water extents, maps of interpolated water heights over the surface water extents are produced. Results indicate a high variability of the water height magnitude that can reach 10 m compared to the lowest water height in the upstream part of the delta during the flood peak in June. Furthermore, the total surface water volume is estimated and shows an annual variation of approximately 8.5 km3 during the whole study period, with

  14. A model to estimate volume change due to radiolytic gas bubbles and thermal expansion in solution reactors

    International Nuclear Information System (INIS)

    Souto, F.J.; Heger, A.S.

    2001-01-01

    To investigate the effects of radiolytic gas bubbles and thermal expansion on the steady-state operation of solution reactors at the power level required for the production of medical isotopes, a calculational model has been developed. To validate this model, including its principal hypotheses, specific experiments at the Los Alamos National Laboratory SHEBA uranyl fluoride solution reactor were conducted. The following sections describe radiolytic gas generation in solution reactors, the equations to estimate the fuel solution volume change due to radiolytic gas bubbles and thermal expansion, the experiments conducted at SHEBA, and the comparison of experimental results and model calculations. (author)

  15. Cross-sectional changes in lung volume measured by electrical impedance tomography are representative for the whole lung in ventilated preterm infants

    NARCIS (Netherlands)

    van der Burg, Pauline S.; Miedema, Martijn; de Jongh, Franciscus H.C.; Frerichs, Inez; van Kaam, Anton H.

    2014-01-01

    Objective: Electrical impedance tomography measures lung volume in a cross-sectional slice of the lung. Whether these cross-sectional volume changes are representative of the whole lung has only been investigated in adults, showing conflicting results. This study aimed to compare cross-sectional and

  16. Cross-sectional changes in lung volume measured by electrical impedance tomography are representative for the whole lung in ventilated preterm infants

    NARCIS (Netherlands)

    van der Burg, Pauline S.; Miedema, Martijn; de Jongh, Frans H.; Frerichs, Inez; van Kaam, Anton H.

    2014-01-01

    Electrical impedance tomography measures lung volume in a cross-sectional slice of the lung. Whether these cross-sectional volume changes are representative of the whole lung has only been investigated in adults, showing conflicting results. This study aimed to compare cross-sectional and whole lung

  17. Stereological brain volume changes in post-weaned socially isolated rats

    DEFF Research Database (Denmark)

    Fabricius, Katrine; Helboe, Lone; Steiniger-Brach, Björn

    2010-01-01

    Rearing rats in isolation after weaning is an environmental manipulation that leads to behavioural and neurochemical alterations that resemble what is seen in schizophrenia. The model is neurodevelopmental in origin and has been used as an animal model of schizophrenia. However, only a few studies...... Lister Hooded rats isolated from postnatal day 25 for 15 weeks. We observed the expected gender differences in total brain volume with males having larger brains than females. Further, we found that isolated males had significantly smaller brains than group-housed controls and larger lateral ventricles...... than controls. However, this was not seen in female rats. Isolated males had a significant smaller hippocampus, dentate gyrus and CA2/3 where isolated females had a significant smaller CA1 compared to controls. Thus, our results indicate that long-term isolation of male rats leads to neuroanatomical...

  18. Detection of skeletal muscle metastasis: torso FDG PET-CT versus contrast-enhanced chest or abdomen CT.

    Science.gov (United States)

    So, Young; Yi, Jeong Geun; Song, Inyoung; Lee, Won Woo; Chung, Hyun Woo; Park, Jeong Hee; Moon, Sung Gyu

    2015-07-01

    Skeletal muscle metastasis (SMM) in cancer patients has not been sufficiently evaluated regarding prevalence and proper method of detection. To determine the prevalence of SMM and compare the diagnostic competencies for SMM of torso F-18 fluorodeoxyglucose (FDG) positron emission tomography-computed tomography (PET-CT) and contrast-enhanced chest or abdomen CT. We investigated 18,225 PET-CT studies of 6359 cancer patients performed from 2005 to 2012. The PET-CT studies describing potential SMM were retrieved and the corresponding medical records were reviewed. The gold standard for SMM was histopathologically-proven SMM or imaging study-based disease progression. The detectability of SMM was compared between PET-CT and contrast-enhanced CT. Twenty-six patients had 84 SMM lesions, representing a SMM prevalence of 0.41%. Lung cancer was the most common SMM-associated malignancy (54%) and the gluteal/pelvic girdle muscle was the most frequently involved SMM site (37%). All 84 SMM lesions were visualized on PET-CT (100%). Of these PET-CT positive 84 SMM lesions, 51 lesions were in the CT field of view (FOV) (61%), whereas 33 lesions were out of the CT FOV (39%). Among these 51 lesions, 17 lesions showed rim-enhancing nodules/masses (33%), eight lesions showed homogeneously enhancing nodules (16%), three lesions showed heterogeneously enhancing nodules (6%), and 23 SMM lesions (45%) were non-diagnostic by CT. All 51 SMM lesions within CT FOV were detected on PET-CT (100%), whereas only 28 were visualized on CT (54.9%), resulting in a significant difference (P SMM was revealed by PET-CT. The prevalence of SMM was as low as 0.41% in the current large cohort of cancer patients. Torso PET-CT was a more competent modality than contrast-enhanced CT in the detection of SMM. © The Foundation Acta Radiologica 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

  19. Classification of bones from MR images in torso PET-MR imaging using a statistical shape model

    International Nuclear Information System (INIS)

    Reza Ay, Mohammad; Akbarzadeh, Afshin; Ahmadian, Alireza; Zaidi, Habib

    2014-01-01

    There have been exclusive features for hybrid PET/MRI systems in comparison with its PET/CT counterpart in terms of reduction of radiation exposure, improved soft-tissue contrast and truly simultaneous and multi-parametric imaging capabilities. However, quantitative imaging on PET/MR is challenged by attenuation of annihilation photons through their pathway. The correction for photon attenuation requires the availability of patient-specific attenuation map, which accounts for the spatial distribution of attenuation coefficients of biological tissues. However, the lack of information on electron density in the MR signal poses an inherent difficulty to the derivation of the attenuation map from MR images. In other words, the MR signal correlates with proton densities and tissue relaxation properties, rather than with electron density and, as such, it is not directly related to attenuation coefficients. In order to derive the attenuation map from MR images at 511 keV, various strategies have been proposed and implemented on prototype and commercial PET/MR systems. Segmentation-based methods generate an attenuation map by classification of T1-weighted or high resolution Dixon MR sequences followed by assignment of predefined attenuation coefficients to various tissue types. Intensity-based segmentation approaches fail to include bones in the attenuation map since the segmentation of bones from conventional MR sequences is a difficult task. Most MR-guided attenuation correction techniques ignore bones owing to the inherent difficulties associated with bone segmentation unless specialized MR sequences such as ultra-short echo (UTE) sequence are utilized. In this work, we introduce a new technique based on statistical shape modeling to segment bones and generate a four-class attenuation map. Our segmentation approach requires a torso bone shape model based on principle component analysis (PCA). A CT-based training set including clearly segmented bones of the torso region

  20. Quantitative Analysis of Torso FDG-PET Scans by Using Anatomical Standardization of Normal Cases from Thorough Physical Examinations.

    Directory of Open Access Journals (Sweden)

    Takeshi Hara

    Full Text Available Understanding of standardized uptake value (SUV of 2-deoxy-2-[18F]fluoro-d-glucose positron emission tomography (FDG-PET depends on the background accumulations of glucose because the SUV often varies the status of patients. The purpose of this study was to develop a new method for quantitative analysis of SUV of FDG-PET scan images. The method included an anatomical standardization and a statistical comparison with normal cases by using Z-score that are often used in SPM or 3D-SSP approach for brain function analysis. Our scheme consisted of two approaches, which included the construction of a normal model and the determination of the SUV scores as Z-score index for measuring the abnormality of an FDG-PET scan image. To construct the normal torso model, all of the normal images were registered into one shape, which indicated the normal range of SUV at all voxels. The image deformation process consisted of a whole body rigid registration of shoulder to bladder region and liver registration and a non-linear registration of body surface by using the thin-plate spline technique. In order to validate usefulness of our method, we segment suspicious regions on FDG-PET images manually, and obtained the Z-scores of the regions based on the corresponding voxels that stores the mean and the standard deviations from the normal model. We collected 243 (143 males and 100 females normal cases to construct the normal model. We also extracted 432 abnormal spots from 63 abnormal cases (73 cancer lesions to validate the Z-scores. The Z-scores of 417 out of 432 abnormal spots were higher than 2.0, which statistically indicated the severity of the spots. In conclusions, the Z-scores obtained by our computerized scheme with anatomical standardization of torso region would be useful for visualization and detection of subtle lesions on FDG-PET scan images even when the SUV may not clearly show an abnormality.

  1. Assessing brain volume changes in older women with breast cancer receiving adjuvant chemotherapy: a brain magnetic resonance imaging pilot study.

    Science.gov (United States)

    Chen, Bihong T; Sethi, Sean K; Jin, Taihao; Patel, Sunita K; Ye, Ningrong; Sun, Can-Lan; Rockne, Russell C; Haacke, E Mark; Root, James C; Saykin, Andrew J; Ahles, Tim A; Holodny, Andrei I; Prakash, Neal; Mortimer, Joanne; Waisman, James; Yuan, Yuan; Somlo, George; Li, Daneng; Yang, Richard; Tan, Heidi; Katheria, Vani; Morrison, Rachel; Hurria, Arti

    2018-05-02

    Cognitive decline is among the most feared treatment-related outcomes of older adults with cancer. The majority of older patients with breast cancer self-report cognitive problems during and after chemotherapy. Prior neuroimaging research has been performed mostly in younger patients with cancer. The purpose of this study was to evaluate longitudinal changes in brain volumes and cognition in older women with breast cancer receiving adjuvant chemotherapy. Women aged ≥ 60 years with stage I-III breast cancer receiving adjuvant chemotherapy and age-matched and sex-matched healthy controls were enrolled. All participants underwent neuropsychological testing with the US National Institutes of Health (NIH) Toolbox for Cognition and brain magnetic resonance imaging (MRI) prior to chemotherapy, and again around one month after the last infusion of chemotherapy. Brain volumes were measured using Neuroreader™ software. Longitudinal changes in brain volumes and neuropsychological scores were analyzed utilizing linear mixed models. A total of 16 patients with breast cancer (mean age 67.0, SD 5.39 years) and 14 age-matched and sex-matched healthy controls (mean age 67.8, SD 5.24 years) were included: 7 patients received docetaxel and cyclophosphamide (TC) and 9 received chemotherapy regimens other than TC (non-TC). There were no significant differences in segmented brain volumes between the healthy control group and the chemotherapy group pre-chemotherapy (p > 0.05). Exploratory hypothesis generating analyses focusing on the effect of the chemotherapy regimen demonstrated that the TC group had greater volume reduction in the temporal lobe (change = - 0.26) compared to the non-TC group (change = 0.04, p for interaction = 0.02) and healthy controls (change = 0.08, p for interaction = 0.004). Similarly, the TC group had a decrease in oral reading recognition scores (change = - 6.94) compared to the non-TC group (change = - 1.21, p for

  2. Hypofractionated stereotactic radiotherapy of acoustic neuroma. Volume changes and hearing results after 89-month median follow-up

    International Nuclear Information System (INIS)

    Kranzinger, Manfred; Fastner, Gerd; Zehentmayr, Franz; Sedlmayer, Felix; Oberascher, Gerhard; Merz, Florian; Rahim, Hassan; Nairz, Olaf

    2014-01-01

    The goal of this work was to evaluate toxicity and local control following hypofractionated stereotactic radiation treatment with special focus on changes in tumor volume and hearing capacity. In all, 29 patients with unilateral acoustic neuroma were treated between 2001 and 2007 within a prospective radiation protocol (7 x 4 Gy ICRU dose). Median tumor volume was 0.9 ml. Follow-up started at 6 months and was repeated annually with MRI volumetry and audiometry. Hearing preservation was defined as preservation of Class A/B hearing according to the guidelines of the American Academy of Otolaryngology (1995). No patient had any intervention after a median imaging follow-up of 89.5 months, one patient showed radiological progression. Transient increase of tumor volume developed in 17/29 patients, whereas 22/29 patients (75.9 %) presented with a volume reduction at last follow-up. A total of 21 patients were eligible for hearing evaluation. Mean pure tone average (PTA) deteriorated from 39.3 to 65.9 dB and mean speech discrimination score (SDS) dropped from 74.3 to 38.1 %. The 5-year actuarial Class A/B hearing preservation rate was 50.0 ± 14.4 %. Radiation increases only minimally, if at all, the hearing deterioration which emerges by observation alone. Presbyacusis is not responsible for this deterioration. Transient tumor enlargement is common. Today radiation of small- and medium-sized acoustic neuroma can be performed with different highly conformal techniques as fractionated treatment or single low-dose radiosurgery with equal results regarding tumor control, hearing preservation, and side effects. Hypofractionation is more comfortable for the patient than conventional regimens and represents a serious alternative to frameless radiosurgery. (orig.) [de

  3. Intereruptive deformation at Three Sisters volcano, Oregon, USA: a strategy for traking volume changes through coupled hydraulic-viscoelastic modeling

    Science.gov (United States)

    Charco, M.; Rodriguez Molina, S.; Gonzalez, P. J.; Negredo, A. M.; Poland, M. P.; Schmidt, D. A.

    2017-12-01

    The Three Sisters volcanic region Oregon (USA) is one of the most active volcanic areas in the Cascade Range and is densely populated with eruptive vents. An extensive area just west of South Sister volcano has been actively uplifting since about 1998. InSAR data from 1992 through 2001 showed an uplift rate in the area of 3-4 cm/yr. Then the deformation rate considerably decreased between 2004 and 2006 as shown by both InSAR and continuous GPS measurements. Once magmatic system geometry and location are determined, a linear inversion of all GPS and InSAR data available is performed in order to estimate the volume changes of the source along the analyzed time interval. For doing so, we applied a technique based on the Truncated Singular Value Decomposition (TSVD) of the Green's function matrix representing the linear inversion. Here, we develop a strategy to provide a cut-off for truncation removing the smallest singular values without too much loose of data resolution against the stability of the method. Furthermore, the strategy will give us a quantification of the uncertainty of the volume change time series. The strength of the methodology resides in allowing the joint inversion of InSAR measurements from multiple tracks with different look angles and three component GPS measurements from multiple sites.Finally, we analyze the temporal behavior of the source volume changes using a new analytical model that describes the process of injecting magma into a reservoir surrounded by a viscoelastic shell. This dynamic model is based on Hagen-Poiseuille flow through a vertical conduit that leads to an increase in pressure within a spherical reservoir and time-dependent surface deformation. The volume time series are compared to predictions from the dynamic model to constrain model parameters, namely characteristic Poiseuille and Maxwell time scales, inlet and outlet injection pressure, and source and shell geometries. The modeling approach used here could be used to

  4. Changes in the Flow-Volume Curve According to the Degree of Stenosis in Patients With Unilateral Main Bronchial Stenosis

    Science.gov (United States)

    Yoo, Jung-Geun; Yi, Chin A; Lee, Kyung Soo; Jeon, Kyeongman; Um, Sang-Won; Koh, Won-Jung; Suh, Gee Young; Chung, Man Pyo; Kwon, O Jung

    2015-01-01

    Objectives The shape of the flow-volume (F-V) curve is known to change to showing a prominent plateau as stenosis progresses in patients with tracheal stenosis. However, no study has evaluated changes in the F-V curve according to the degree of bronchial stenosis in patients with unilateral main bronchial stenosis. Methods We performed an analysis of F-V curves in 29 patients with unilateral bronchial stenosis with the aid of a graphic digitizer between January 2005 and December 2011. Results The primary diseases causing unilateral main bronchial stenosis were endobronchial tuberculosis (86%), followed by benign bronchial tumor (10%), and carcinoid (3%). All unilateral main bronchial stenoses were classified into one of five grades (I, ≤25%; II, 26%-50%; III, 51%-75%; IV, 76%-90%; V, >90% to near-complete obstruction without ipsilateral lung collapse). A monophasic F-V curve was observed in patients with grade I stenosis and biphasic curves were observed for grade II-IV stenosis. Both monophasic (81%) and biphasic shapes (18%) were observed in grade V stenosis. After standardization of the biphasic shape of the F-V curve, the breakpoints of the biphasic curve moved in the direction of high volume (x-axis) and low flow (y-axis) according to the progression of stenosis. Conclusion In unilateral bronchial stenosis, a biphasic F-V curve appeared when bronchial stenosis was >25% and disappeared when obstruction was near complete. In addition, the breakpoint moved in the direction of high volume and low flow with the progression of stenosis. PMID:26045916

  5. Motion of bones and volume changes in the neurocranium after craniectomy in Crouzon's disease. A roentgen stereometric study.

    Science.gov (United States)

    Rune, B; Selvik, G; Kreiborg, S; Sarnäs, K V; Kågström, E

    1979-04-01

    Craniectomy was performed on a boy with Crouzon's disease at 22 months of age. Metallic implants (tantalum balls, 0.5 mm in diameter) were inserted in the calvaria during surgery, and the child was examined postoperatively by roentgen stereometry at intervals of about 100 days (total observation time, 309 days). The thyroid radiation dose was 250 muGy for one examination. The effect of craniectomy was recorded with a high degree of accuracy in terms of motion of bones and volume changes in the calvaria. Expansion occurred almost entirely through motion of free bone flaps in the frontal region, while a linear craniectomy in the region of the sagittal suture caused small changes. The rate of expansion decreased rapidly and stabilization was recorded about 250 days after surgery.

  6. Confined-Volume Effect on the Thermal Properties of Encapsulated Phase Change Materials for Thermal Energy Storage.

    Science.gov (United States)

    De Castro, Paula F; Ahmed, Adham; Shchukin, Dmitry G

    2016-03-18

    We have encapsulated the heat exchange material, n-docosane, into polyurethane capsules of different sizes. Decreasing the size of the capsules leads to changes of the crystallinity of phase-change material as well as melting/crystallization temperature. The novelty of the paper includes 1) protection of the nanostructured energy-enriched materials against environment during storage and controlled release of the encapsulated energy on demand and 2) study of the structure and surface-to-volume properties of the energy-enriched materials dispersed in capsules of different sizes. The stability of energy nanomaterials, influence of capsule diameter on their energy capacity, homogeneity and operation lifetime are investigated. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. Detection of atomic scale changes in the free volume void size of three-dimensional colorectal cancer cell culture using positron annihilation lifetime spectroscopy.

    Science.gov (United States)

    Axpe, Eneko; Lopez-Euba, Tamara; Castellanos-Rubio, Ainara; Merida, David; Garcia, Jose Angel; Plaza-Izurieta, Leticia; Fernandez-Jimenez, Nora; Plazaola, Fernando; Bilbao, Jose Ramon

    2014-01-01

    Positron annihilation lifetime spectroscopy (PALS) provides a direct measurement of the free volume void sizes in polymers and biological systems. This free volume is critical in explaining and understanding physical and mechanical properties of polymers. Moreover, PALS has been recently proposed as a potential tool in detecting cancer at early stages, probing the differences in the subnanometer scale free volume voids between cancerous/healthy skin samples of the same patient. Despite several investigations on free volume in complex cancerous tissues, no positron annihilation studies of living cancer cell cultures have been reported. We demonstrate that PALS can be applied to the study in human living 3D cell cultures. The technique is also capable to detect atomic scale changes in the size of the free volume voids due to the biological responses to TGF-β. PALS may be developed to characterize the effect of different culture conditions in the free volume voids of cells grown in vitro.

  8. Effects of Hormone Therapy on Brain Volumes Changes of Postmenopausal Women Revealed by Optimally-Discriminative Voxel-Based Morphometry.

    Directory of Open Access Journals (Sweden)

    Tianhao Zhang

    Full Text Available The Women's Health Initiative Memory Study Magnetic Resonance Imaging (WHIMS-MRI provides an opportunity to evaluate how menopausal hormone therapy (HT affects the structure of older women's brains. Our earlier work based on region of interest (ROI analysis demonstrated potential structural changes underlying adverse effects of HT on cognition. However, the ROI-based analysis is limited in statistical power and precision, and cannot provide fine-grained mapping of whole-brain changes.We aimed to identify local structural differences between HT and placebo groups from WHIMS-MRI in a whole-brain refined level, by using a novel method, named Optimally-Discriminative Voxel-Based Analysis (ODVBA. ODVBA is a recently proposed imaging pattern analysis approach for group comparisons utilizing a spatially adaptive analysis scheme to accurately locate areas of group differences, thereby providing superior sensitivity and specificity to detect the structural brain changes over conventional methods.Women assigned to HT treatments had significant Gray Matter (GM losses compared to the placebo groups in the anterior cingulate and the adjacent medial frontal gyrus, and the orbitofrontal cortex, which persisted after multiple comparison corrections. There were no regions where HT was significantly associated with larger volumes compared to placebo, although a trend of marginal significance was found in the posterior cingulate cortical area. The CEE-Alone and CEE+MPA groups, although compared with different placebo controls, demonstrated similar effects according to the spatial patterns of structural changes.HT had adverse effects on GM volumes and risk for cognitive impairment and dementia in older women. These findings advanced our understanding of the neurobiological underpinnings of HT effects.

  9. Ice volume and climate changes from a 6000 year sea-level record in French Polynesia.

    Science.gov (United States)

    Hallmann, N; Camoin, G; Eisenhauer, A; Botella, A; Milne, G A; Vella, C; Samankassou, E; Pothin, V; Dussouillez, P; Fleury, J; Fietzke, J

    2018-01-18

    Mid- to late-Holocene sea-level records from low-latitude regions serve as an important baseline of natural variability in sea level and global ice volume prior to the Anthropocene. Here, we reconstruct a high-resolution sea-level curve encompassing the last 6000 years based on a comprehensive study of coral microatolls, which are sensitive low-tide recorders. Our curve is based on microatolls from several islands in a single region and comprises a total of 82 sea-level index points. Assuming thermosteric contributions are negligible on millennial time scales, our results constrain global ice melting to be 1.5-2.5 m (sea-level equivalent) since ~5500 years before present. The reconstructed curve includes isolated rapid events of several decimetres within a few centuries, one of which is most likely related to loss from the Antarctic ice sheet mass around 5000 years before present. In contrast, the occurrence of large and flat microatolls indicates periods of significant sea-level stability lasting up to ~300 years.

  10. The assessment of changes in brain volume using combined linear measurements

    International Nuclear Information System (INIS)

    Gomori, J.M.; Steiner, I.; Melamed, E.; Cooper, G.

    1984-01-01

    All linear measurements employed for evaluation of brain atrophy, were performed on 148 computed tomograms of patients aged 28 to 84 without evidence of any nervous system disorder. These included size of lateral, third and fourth ventricles, width of the Sylvian and frontal interhemispheric fissures and cortical sulci and size of the pre-pontine cistern. Various parameters indicated decrease in brain mass with age. Since the atrophic process is a diffuse phenomenon, integration of several measurements evaluating separate brain regions was made. The bicaudate ratio and the Sylvian fissure ratio (representing both central and cortical atrophy) were combined arithmetically, resulting in a correlation of 0.6390 with age (p<0.0005). With a computed canonical correlation analysis: a formula was obtained which combined measurements of the lateral and third ventricles, the Sylvian fissure and the pre-pontine cistern. This formula yealded a correlation of 0.67795 (p<0.0005). These linear measurements will enable simple and reliable assessment of reduction in brain volume during the normal aging process and in disorders accompanied by brain atrophy. (orig.)

  11. Response of faults to climate-driven changes in ice and water volumes on Earth's surface.

    Science.gov (United States)

    Hampel, Andrea; Hetzel, Ralf; Maniatis, Georgios

    2010-05-28

    Numerical models including one or more faults in a rheologically stratified lithosphere show that climate-induced variations in ice and water volumes on Earth's surface considerably affect the slip evolution of both thrust and normal faults. In general, the slip rate and hence the seismicity of a fault decreases during loading and increases during unloading. Here, we present several case studies to show that a postglacial slip rate increase occurred on faults worldwide in regions where ice caps and lakes decayed at the end of the last glaciation. Of note is that the postglacial amplification of seismicity was not restricted to the areas beneath the large Laurentide and Fennoscandian ice sheets but also occurred in regions affected by smaller ice caps or lakes, e.g. the Basin-and-Range Province. Our results do not only have important consequences for the interpretation of palaeoseismological records from faults in these regions but also for the evaluation of the future seismicity in regions currently affected by deglaciation like Greenland and Antarctica: shrinkage of the modern ice sheets owing to global warming may ultimately lead to an increase in earthquake frequency in these regions.

  12. Gray matter volume changes in chronic subcortical stroke: A cross-sectional study

    Directory of Open Access Journals (Sweden)

    Qingqing Diao

    2017-01-01

    Full Text Available This study aimed to investigate the effects of lesion side and degree of motor recovery on gray matter volume (GMV difference relative to healthy controls in right-handed subcortical stroke. Structural MRI data were collected in 97 patients with chronic subcortical ischemic stroke and 79 healthy controls. Voxel-wise GMV analysis was used to investigate the effects of lesion side and degree of motor recovery on GMV difference in right-handed chronic subcortical stroke patients. Compared with healthy controls, right-lesion patients demonstrated GMV increase (P < 0.05, voxel-wise false discovery rate correction in the bilateral paracentral lobule (PCL and supplementary motor area (SMA and the right middle occipital gyrus (MOG; while left-lesion patients did not exhibit GMV difference under the same threshold. Patients with complete and partial motor recovery showed similar degree of GMV increase in right-lesion patients. However, the motor recovery was correlated with the GMV increase in the bilateral SMA in right-lesion patients. These findings suggest that there exists a lesion-side effect on GMV difference relative to healthy controls in right-handed patients with chronic subcortical stroke. The GMV increase in the SMA may facilitate motor recovery in subcortical stroke patients.

  13. Concurrent validity and reliability of torso-worn inertial measurement unit for jump power and height estimation.

    Science.gov (United States)

    Rantalainen, Timo; Gastin, Paul B; Spangler, Rhys; Wundersitz, Daniel

    2018-09-01

    The purpose of the present study was to evaluate the concurrent validity and test-retest repeatability of torso-worn IMU-derived power and jump height in a counter-movement jump test. Twenty-seven healthy recreationally active males (age, 21.9 [SD 2.0] y, height, 1.76 [0.7] m, mass, 73.7 [10.3] kg) wore an IMU and completed three counter-movement jumps a week apart. A force platform and a 3D motion analysis system were used to concurrently measure the jumps and subsequently derive power and jump height (based on take-off velocity and flight time). The IMU significantly overestimated power (mean difference = 7.3 W/kg; P jump heights exhibited poorer concurrent validity (ICC = 0.72 to 0.78) and repeatability (ICC = 0.68) than flight-time-derived jump heights, which exhibited excellent validity (ICC = 0.93 to 0.96) and reliability (ICC = 0.91). Since jump height and power are closely related, and flight-time-derived jump height exhibits excellent concurrent validity and reliability, flight-time-derived jump height could provide a more desirable measure compared to power when assessing athletic performance in a counter-movement jump with IMUs.

  14. Changes in pharyngeal constrictor volumes during head and neck radiation therapy: Implications for dose delivery

    Directory of Open Access Journals (Sweden)

    Akila Kumarasiri

    2017-01-01

    Conclusion: The patients underwent considerable anatomical changes to PCM during H and N RT. However, the resultant increase in dose to PCM was minor to moderate. PCM thickness measured at C3 level is a good predictor for the mean dose increase to PCM.

  15. The Employment Impact of Technological Change. Technology and the American Economy, Appendix Volume II.

    Science.gov (United States)

    National Commission on Technology, Automation and Economic Progress, Washington, DC.

    Eleven descriptive studies prepared by independent experts and dealing with the employment impact of technological change are presented. Part I contains (1) an analysis, at the establishment level, of employment-increasing growth of output and employment-decreasing growth of output per man-hour, (2) case studies of the elapsed time involved in the…

  16. Adjusting to Change. Technology and the American Economy, Appendix, Volume III.

    Science.gov (United States)

    National Commission on Technology, Automation and Economic Progress, Washington, DC.

    Seven studies dealing with adjustment to technological change which were done by independent experts are presented. "Programs in Aid of the Poor," by Sar A. Levitan assesses the state of social insurance, public assistance, the poverty program and other assistance to the poor and compares them to current proposals as the negative income…

  17. Statements Relating to the Impact of Technological Change. Technology and the American Economy, Appendix, Volume VI.

    Science.gov (United States)

    National Commission on Technology, Automation and Economic Progress, Washington, DC.

    Forty-seven statements by industrial and business spokesmen, union and association representatives, and professors concern the broad impact of technological change on individuals, establishments, and society in general. Some of the longer presentations are (1) "The Poverty and Unemployment Crisis," by Walter Buckingham, (2) "Technological…

  18. Tectonics, orbital forcing, global climate change, and human evolution in Africa: introduction to the African paleoclimate special volume.

    Science.gov (United States)

    Maslin, Mark A; Christensen, Beth

    2007-11-01

    The late Cenozoic climate of Africa is a critical component for understanding human evolution. African climate is controlled by major tectonic changes, global climate transitions, and local variations in orbital forcing. We introduce the special African Paleoclimate Issue of the Journal of Human Evolution by providing a background for and synthesis of the latest work relating to the environmental context for human evolution. Records presented in this special issue suggest that the regional tectonics, appearance of C(4) plants in East Africa, and late Cenozoic global cooling combined to produce a long-term drying trend in East Africa. Of particular importance is the uplift associated with the East African Rift Valley formation, which altered wind flow patterns from a more zonal to more meridinal direction. Results in this volume suggest a marked difference in the climate history of southern and eastern Africa, though both are clearly influenced by the major global climate thresholds crossed in the last 3 million years. Papers in this volume present lake, speleothem, and marine paleoclimate records showing that the East African long-term drying trend is punctuated by episodes of short, alternating periods of extreme wetness and aridity. These periods of extreme climate variability are characterized by the precession-forced appearance and disappearance of large, deep lakes in the East African Rift Valley and paralleled by low and high wind-driven dust loads reaching the adjacent ocean basins. Dating of these records show that over the last 3 million years such periods only occur at the times of major global climatic transitions, such as the intensification of Northern Hemisphere Glaciation (2.7-2.5 Ma), intensification of the Walker Circulation (1.9-1.7 Ma), and the Mid-Pleistocene Revolution (1-0.7 Ma). Authors in this volume suggest this onset occurs as high latitude forcing in both Hemispheres compresses the Intertropical Convergence Zone so that East Africa

  19. The DTIC Review. Volume 1, Number 1: Nuclear Proliferation and Deterrence in a Changing Political World

    Science.gov (United States)

    1995-08-01

    Mathematical Expectation" by David Schmeidler and Peter Wakker, "Expected Utility Hypothesis" by Mark Machina, "Rational Behavior" by Amartya Sen ...other regional adversaries are not secure and, hence, are highly sen - sitive to this form of pressure. The question is whether such threats can be used...Warsaw Pact." Moreover, conventional military capabilities are constantly changing through advances in armor, avionics, sen - sors, munitions. etc

  20. Numerical investigation on critical heat flux and coolant volume required for transpiration cooling with phase change

    International Nuclear Information System (INIS)

    He, Fei; Wang, Jianhua

    2014-01-01

    Highlights: • Five states during the transpiration cooling are discussed. • A suit of applicable program is developed. • The variations of the thickness of two-phase region and the pressure are analyzed. • The relationship between heat flux and coolant mass flow rate is presented. • An approach is given to define the desired case of transpiration cooling. - Abstract: The mechanism of transpiration cooling with liquid phase change is numerically investigated to protect the thermal structure exposed to extremely high heat flux. According to the results of theoretical analysis, there is a lower critical and an upper critical external heat flux corresponding a certain coolant mass flow rate, between the two critical values, the phase change of liquid coolant occurs within porous structure. A strongly applicable self-edit program is developed to solve the states of fluid flow and heat transfer probably occurring during the phase change procedure. The distributions of temperature and saturation in these states are presented. The variations of the thickness of two-phase region and the pressure including capillary are analyzed, and capillary pressure is found to be the main factor causing pressure change. From the relationships between the external heat flux and coolant mass flow rate obtained at different cooling cases, an approach is given to estimate the maximal heat flux afforded and the minimal coolant consumption required by the desired case of transpiration cooling. Thus the pressure and coolant consumption required in a certain thermal circumstance can be determined, which are important in the practical application of transpiration cooling

  1. Modulation of Kir4.1 and Kir4.1-Kir5.1 channels by small changes in cell volume

    DEFF Research Database (Denmark)

    Soe, Rikke; Macaulay, Nanna; Klaerke, Dan Arne

    2009-01-01

    in Kir4.1 and Kir4.1-Kir5.1 currents upon swelling of the oocytes and a reduction in the current when the oocytes were shrunk. The volume-dependent changes in channel activity were not due to changes in the kinetics of the channels. These findings implicate a putative functional interaction between...... the Kir channels and aquaporins via small, fast cell volume changes in the glial cells....... channels and aquaporins is therefore debated. To test a possible volume-sensitivity of the Kir channels, the Kir4.1 or Kir4.1-Kir5.1 channels were expressed in Xenopus oocytes with or without co-expression of aquaporins and subsequently exposed to cell volume alterations. Our results show an increase...

  2. Mapping reservoir volume changes during cyclic steam stimulation using tiltmeter-based surface deformation measurements

    Energy Technology Data Exchange (ETDEWEB)

    Du, J.; Davis, E.J.; Roadarmel, W.H.; Wolhart, S.L.; Marsic, S.; Gusek, R.; Wright, C.A. [Society of Petroleum Engineers, Richardson, TX (United States)]|[Pinnacle Technologies Inc., Houston, TX (United States); Brissenden, S.J.; McGillivray, P. [Shell Canada Ltd., Calgary, AB (Canada). Calgary Research Centre; Bourne, S.; Hofstra, P. [Shell International E and P, Calgary, AB (Canada)

    2005-11-01

    Surface deformation measurements have been effectively used to monitor production, waterflooding, waste injection and steam flooding in oil fields, and in cyclic steam stimulation (CSS) applications. It was shown that further information can be obtained from this technique by inverting the surface deformation for the volumetric deformation at the reservoir level, so that the aerial distribution of volumetric distribution can be identified. A poroelastic model calculated deformation resulting from volumetric changes in the reservoir. A linear geophysical model was then formulated to invert the reservoir volumetric deformation from the measured surface deformation. Constraints were applied to resolve the inversion problem. Theoretical surface deformation was calculated after each inversion from the inverted volumetric deformation distribution which best fit the measured information data, or tilt, at the surface. The technique was then applied to real data from a CSS injection project at Shell Canada's Peace River development in northern Alberta, where several pads of horizontal wells have been developed. A total of 50 tiltmeters were used to monitor half of Pad A and 70 tiltmeters were used to monitor Pad B. Monitoring was used to identify and characterize any hydraulic fracturing that was contributing to injection mechanisms in the reservoir. It was noted that inverting the measured surface tilt for the volumetric change at reservoir levels improved the ability to interpret reservoir processes. It was observed that volumetric changes can be non-uniform with some pad areas deforming more than others. It was concluded that deformation-based, reservoir-level monitoring has proven helpful in ongoing efforts to optimize such variables as the length of well laterals, injection rates, lateral spacing and cycle times. 10 refs., 32 figs.

  3. Changing times. Southwest Energy-Minerals Conference Proceedings, Volumes 1 and 2

    Energy Technology Data Exchange (ETDEWEB)

    None

    1977-01-01

    This conference was held at the Albuquerque Convention Center, Albuquerque, NM, Nov. 2 and 3, 1977. It was sponsored by the Bureau of Land Management, U.S. Dept. of the Interior. It contains articles on the leasing of coal deposits (changes and modifications of leasing policy, environmental impact statements, U.S. energy policy (NEP), prices of gas and oil), New Mexico's energy consumption (by the Governor), transport of energy (Santa Fe railroad's plans), the energy crisis and proposed solutions, energy supplies and environmental problems, energy problems of agriculture (fuels, fertilizers and water energy requirements are greater than the energy in the food produced; possibility of biomass conversion, photosynthetic efficiency of using sunlight in arid lands), energy project financing, a review of the recent Law of the Sea conferences (1967 to date) (mining projects), growth economy as no growth and relation to energy supplies and environmental problems, natural gas and petroleum industries (divestiture problems, reserves), raw materials stockpiles (national experience, changing targets), the mining industry and its reserves of metals, taxation, etc.). (LTN)

  4. Effect of long-term isometric training on core/torso stiffness.

    Science.gov (United States)

    Lee, Benjamin C Y; McGill, Stuart M

    2015-06-01

    Although core stiffness enhances athletic performance traits, controversy exists regarding the effectiveness of isometric vs. dynamic core training methods. This study aimed to determine whether long-term changes in stiffness can be trained, and if so, what is the most effective method. Twenty-four healthy male subjects (23 ± 3 years; 1.8 ± 0.06 m; 77.5 ± 10.8 kg) were recruited for passive and active stiffness measurements before and after a 6-week core training intervention. Twelve subjects (22 ± 2 years; 1.8 ± 0.08 m; 78.3 ± 12.3 kg) were considered naive to physical and core exercise. The other 12 subjects (24 ± 3 years; 1.8 ± 0.05 m; 76.8 ± 9.7 kg) were Muay Thai athletes (savvy). A repeated-measures design compared core training methods (isometric vs. dynamic, with a control group) and subject training experience (naive vs. savvy) before and after a 6-week training period. Passive stiffness was assessed on a "frictionless" bending apparatus and active stiffness assessed through a quick release mechanism. Passive stiffness increased after the isometric training protocol. Dynamic training produced a smaller effect, and as expected, there was no change in the control group. Active stiffness did not change in any group. Comparisons between subject and training groups did not reveal any interactions. Thus, an isometric training approach was superior in terms of enhancing core stiffness. This is important since increased core stiffness enhances load bearing ability, arrests painful vertebral micromovements, and enhances ballistic distal limb movement. This may explain the efficacy reported for back and knee injury reduction.

  5. Comparison of grey matter volume and thickness for analysing cortical changes in chronic schizophrenia: a matter of surface area, grey/white matter intensity contrast, and curvature.

    Science.gov (United States)

    Kong, Li; Herold, Christina J; Zöllner, Frank; Salat, David H; Lässer, Marc M; Schmid, Lena A; Fellhauer, Iven; Thomann, Philipp A; Essig, Marco; Schad, Lothar R; Erickson, Kirk I; Schröder, Johannes

    2015-02-28

    Grey matter volume and cortical thickness are the two most widely used measures for detecting grey matter morphometric changes in various diseases such as schizophrenia. However, these two measures only share partial overlapping regions in identifying morphometric changes. Few studies have investigated the contributions of the potential factors to the differences of grey matter volume and cortical thickness. To investigate this question, 3T magnetic resonance images from 22 patients with schizophrenia and 20 well-matched healthy controls were chosen for analyses. Grey matter volume and cortical thickness were measured by VBM and Freesurfer. Grey matter volume results were then rendered onto the surface template of Freesurfer to compare the differences from cortical thickness in anatomical locations. Discrepancy regions of the grey matter volume and thickness where grey matter volume significantly decreased but without corresponding evidence of cortical thinning involved the rostral middle frontal, precentral, lateral occipital and superior frontal gyri. Subsequent region-of-interest analysis demonstrated that changes in surface area, grey/white matter intensity contrast and curvature accounted for the discrepancies. Our results suggest that the differences between grey matter volume and thickness could be jointly driven by surface area, grey/white matter intensity contrast and curvature. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  6. Usefulness of Intravital Multiphoton Microscopy in Visualizing Study of Mouse Cochlea and Volume Changes in the Scala Media.

    Science.gov (United States)

    Ju, Hyun Mi; Lee, Sun Hee; Kong, Tae Hoon; Kwon, Seung-Hae; Choi, Jin Sil; Seo, Young Joon

    2017-01-01

    Conventional microscopy has limitations in viewing the cochlear microstructures due to three-dimensional spiral structure and the overlying bone. But these issues can be overcome by imaging the cochlea in vitro with intravital multiphoton microscopy (MPM). By using near-infrared lasers for multiphoton excitation, intravital MPM can detect endogenous fluorescence and second harmonic generation of tissues. In this study, we used intravital MPM to visualize various cochlear microstructures without any staining and non-invasively analyze the volume changes of the scala media (SM) without removing the overlying cochlear bone. The intravital MPM images revealed various tissue types, ranging from thin membranes to dense bone, as well as the spiral ganglion beneath the cochlear bone. The two-dimensional, cross-sectional, and serial z-stack intravital MPM images also revealed the spatial dilation of the SM in the temporal bone of pendrin-deficient mice. These findings suggest that intravital MPM might serve as a new method for obtaining microanatomical information regarding the cochlea, similar to standard histopathological analyses in the animal study for the cochlea. Given the capability of intravital MPM for detecting an increase in the volume of the SM in pendrin-deficient mice, it might be a promising new tool for assessing the pathophysiology of hearing loss in the future.

  7. Drug-class-specific changes in the volume and cost of antidiabetic medications in Poland between 2012 and 2015.

    Science.gov (United States)

    Śliwczyński, Andrzej; Brzozowska, Melania; Jacyna, Andrzej; Iltchev, Petre; Iwańczuk, Tymoteusz; Wierzba, Waldemar; Marczak, Michał; Orlewska, Katarzyna; Szymański, Piotr; Orlewska, Ewa

    2017-01-01

    to investigate the drug-class-specific changes in the volume and cost of antidiabetic medications in Poland in 2012-2015. This retrospective analysis was conducted based on the National Health Fund database covering an entire Polish population. The volume of antidiabetic medications is reported according to ATC/DDD methodology, costs-in current international dollars, based on purchasing power parity. During a 4-year observational period the number of patients, consumption of antidiabetic drugs and costs increased by 17%, 21% and 20%, respectively. Biguanides are the basic diabetes medication with a 39% market share. The insulin market is still dominated by human insulins, new antidiabetics (incretins, thiazolidinediones) are practically absent. Insulins had the largest share in diabetes medications expenditures (67% in 2015). The increase in antidiabetic medications costs over the analysed period of time was mainly caused by the increased use of insulin analogues. The observed tendencies correspond to the evidence-based HTA recommendations. The reimbursement status, the ratio of cost to clinical outcomes and data on the long-term safety have a deciding impact on how a drug is used.

  8. Usefulness of Intravital Multiphoton Microscopy in Visualizing Study of Mouse Cochlea and Volume Changes in the Scala Media

    Directory of Open Access Journals (Sweden)

    Hyun Mi Ju

    2017-07-01

    Full Text Available Conventional microscopy has limitations in viewing the cochlear microstructures due to three-dimensional spiral structure and the overlying bone. But these issues can be overcome by imaging the cochlea in vitro with intravital multiphoton microscopy (MPM. By using near-infrared lasers for multiphoton excitation, intravital MPM can detect endogenous fluorescence and second harmonic generation of tissues. In this study, we used intravital MPM to visualize various cochlear microstructures without any staining and non-invasively analyze the volume changes of the scala media (SM without removing the overlying cochlear bone. The intravital MPM images revealed various tissue types, ranging from thin membranes to dense bone, as well as the spiral ganglion beneath the cochlear bone. The two-dimensional, cross-sectional, and serial z-stack intravital MPM images also revealed the spatial dilation of the SM in the temporal bone of pendrin-deficient mice. These findings suggest that intravital MPM might serve as a new method for obtaining microanatomical information regarding the cochlea, similar to standard histopathological analyses in the animal study for the cochlea. Given the capability of intravital MPM for detecting an increase in the volume of the SM in pendrin-deficient mice, it might be a promising new tool for assessing the pathophysiology of hearing loss in the future.

  9. Assessing high altitude glacier thickness, volume and area changes using field, GIS and remote sensing techniques: the case of Nevado Coropuna (Peru

    Directory of Open Access Journals (Sweden)

    P. Peduzzi

    2010-08-01

    Full Text Available Higher temperatures and changes in precipitation patterns have induced an acute decrease in Andean glaciers, thus leading to additional stress on water supply. To adapt to climate changes, local governments need information on the rate of glacier area and volume losses and on current ice thickness. Remote sensing analyses of Coropuna glacier (Peru delineate an acute glaciated area decline between 1955 and 2008. We tested how volume changes can be estimated with remote sensing and GIS techniques using digital elevation models derived from both topographic maps and satellite images. Ice thickness was measured in 2004 using a Ground Penetrating Radar coupled with a Ground Positioning System during a field expedition. It provided profiles of ice thickness on different slopes, orientations and altitudes. These were used to model the current glacier volume using Geographical Information System and statistical multiple regression techniques. The results revealed a significant glacier volume loss; however the uncertainty is higher than the measured volume loss. We also provided an estimate of the remaining volume. The field study provided the scientific evidence needed by COPASA, a local Peruvian NGO, and GTZ, the German international cooperation agency, in order to alert local governments and communities and guide them in adopting new climate change adaptation policies.

  10. Relationship between the changes in blood flow and volume in the finger during a Braille character discrimination task.

    Science.gov (United States)

    Murata, J; Murata, S; Soma, M; Nakae, H; Sato, Y; Kogo, H; Umeki, N

    2017-11-01

    We hypothesized that skin blood flow (SBF) of fingers are modulated during concentrated finger perception and that the changes in SBF reflect fluctuations in finger volume (FV). The aim of this study, therefore, was examine the relationship between the changes in SBF and FV during Braille reading. We measured SBF of the finger, cutaneous vascular conductance (CVC), FV, and arterial blood pressure during Braille reading performed under blind conditions in thirty healthy subjects. The subjects were instructed to read a flat plate with raised letters (Braille reading) for 15 seconds using their forefinger, and to touch a blank plate as a control for the Braille discrimination procedure. Arterial blood pressure slightly increased during Braille reading but remained unchanged during the touching of the blank plate. SBF, CVC, and FV were reduced during Braille reading (decreased by -26%, -29%, and -0.3 mL/100 mL respectively). Furthermore, a significant relationship was observed between the changes in SBF and FV (r=.613) during Braille reading. These results suggested that SBF of fingers is modulated during concentrated finger perception, and that the variability of blood flow reflects the response in FV. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  11. Relation between the Change in Mean Platelet Volume and Clopidogrel Resistance in Patients Undergoing Percutaneous Coronary Intervention.

    Science.gov (United States)

    Koh, Young-Youp; Kim, Hyung Ho; Choi, Dong-Hyun; Lee, Young-Min; Ki, Young-Jae; Kang, Seong-Ho; Park, Geon; Chung, Joong-Wha; Chang, Kyong-Sig; Hong, Soon-Pyo

    2015-01-01

    We aimed to determine the association between the change in mean platelet volume (MPV) over time and aspirin/ clopidogrel resistance in patients undergoing percutaneous coronary intervention (PCI). The MPV and platelet function were analysed in 302 patients who underwent PCI. MPV changes were associated with increased aspirin reaction units (ARU, r = 0.114; P = 0.047), increased P2Y12 reaction units (PRU, r = 0.193; P = 0.001), and decreased P2Y12% inhibition (PI%, r = - 0.273; P resistant group (≥235 PRU or ≤15% of PI%) showed a significantly higher positive change in MPV (ΔMPV) values than the clopidogrel responder group (0.53 ± 0.78 vs. 0.13 ± 0.69 fL, P resistant and responder groups were 72.6% and 59.3%, respectively. After adjusting for traditional risk factors, the odds ratio in the clopidogrel resistant group with ΔMPV ≥0.2 fL was 4.10 (95% confidence interval; 1.84-9.17). In conclusion, ΔMPV was associated with PRU and PI%; a positive ΔMPV was an independent predictive marker for clopidogrel resistance after PCI.

  12. Genetic influences on individual differences in longitudinal changes in global and subcortical brain volumes: Results of the ENIGMA plasticity working group.

    Science.gov (United States)

    Brouwer, Rachel M; Panizzon, Matthew S; Glahn, David C; Hibar, Derrek P; Hua, Xue; Jahanshad, Neda; Abramovic, Lucija; de Zubicaray, Greig I; Franz, Carol E; Hansell, Narelle K; Hickie, Ian B; Koenis, Marinka M G; Martin, Nicholas G; Mather, Karen A; McMahon, Katie L; Schnack, Hugo G; Strike, Lachlan T; Swagerman, Suzanne C; Thalamuthu, Anbupalam; Wen, Wei; Gilmore, John H; Gogtay, Nitin; Kahn, René S; Sachdev, Perminder S; Wright, Margaret J; Boomsma, Dorret I; Kremen, William S; Thompson, Paul M; Hulshoff Pol, Hilleke E

    2017-09-01

    Structural brain changes that occur during development and ageing are related to mental health and general cognitive functioning. Individuals differ in the extent to which their brain volumes change over time, but whether these differences can be attributed to differences in their genotypes has not been widely studied. Here we estimate heritability (h 2 ) of changes in global and subcortical brain volumes in five longitudinal twin cohorts from across the world and in different stages of the lifespan (N = 861). Heritability estimates of brain changes were significant and ranged from 16% (caudate) to 42% (cerebellar gray matter) for all global and most subcortical volumes (with the exception of thalamus and pallidum). Heritability estimates of change rates were generally higher in adults than in children suggesting an increasing influence of genetic factors explaining individual differences in brain structural changes with age. In children, environmental influences in part explained individual differences in developmental changes in brain structure. Multivariate genetic modeling showed that genetic influences of change rates and baseline volume significantly overlapped for many structures. The genetic influences explaining individual differences in the change rate for cerebellum, cerebellar gray matter and lateral ventricles were independent of the genetic influences explaining differences in their baseline volumes. These results imply the existence of genetic variants that are specific for brain plasticity, rather than brain volume itself. Identifying these genes may increase our understanding of brain development and ageing and possibly have implications for diseases that are characterized by deviant developmental trajectories of brain structure. Hum Brain Mapp 38:4444-4458, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  13. Three-dimensional volume rendering of tibiofibular joint space and quantitative analysis of change in volume due to tibiofibular syndesmosis diastases

    International Nuclear Information System (INIS)

    Taser, F.; Shafiq, Q.; Ebraheim, N.A.

    2006-01-01

    The diagnosis of ankle syndesmosis injuries is made by various imaging techniques. The present study was undertaken to examine whether the three-dimensional reconstruction of axial CT images and calculation of the volume of tibiofibular joint space enhances the sensitivity of diastases diagnoses or not. Six adult cadaveric ankle specimens were used for spiral CT-scan assessment of tibiofibular syndesmosis. After the specimens were dissected, external fixation was performed and diastases of 1, 2, and 3 mm was simulated by a precalibrated device. Helical CT scans were obtained with 1.0-mm slice thickness. The data was transferred to the computer software AcquariusNET. Then the contours of the tibiofibular syndesmosis joint space were outlined on each axial CT slice and the collection of these slices were stacked using the computer software AutoCAD 2005, according to the spatial arrangement and geometrical coordinates between each slice, to produce a three-dimensional reconstruction of the joint space. The area of each slice and the volume of the entire tibiofibular joint space were calculated. The tibiofibular joint space at the 10th-mm slice level was also measured on axial CT scan images at normal, 1, 2 and 3-mm joint space diastases. The three-dimensional volume-rendering of the tibiofibular syndesmosis joint space from the spiral CT data demonstrated the shape of the joint space and has been found to be a sensitive method for calculating joint space volume. We found that, from normal to 1 mm, a 1-mm diastasis increases approximately 43% of the joint space volume, while from 1 to 3 mm, there is about a 20% increase for each 1-mm increase. Volume calculation using this method can be performed in cases of syndesmotic instability after ankle injuries and for preoperative and postoperative evaluation of the integrity of the tibiofibular syndesmosis. (orig.)

  14. Repeated Structural Imaging Reveals Nonlinear Progression of Experience-Dependent Volume Changes in Human Motor Cortex.

    Science.gov (United States)

    Wenger, Elisabeth; Kühn, Simone; Verrel, Julius; Mårtensson, Johan; Bodammer, Nils Christian; Lindenberger, Ulman; Lövdén, Martin

    2017-05-01

    Evidence for experience-dependent structural brain change in adult humans is accumulating. However, its time course is not well understood, as intervention studies typically consist of only 2 imaging sessions (before vs. after training). We acquired up to 18 structural magnetic resonance images over a 7-week period while 15 right-handed participants practiced left-hand writing and drawing. After 4 weeks, we observed increases in gray matter of both left and right primary motor cortices relative to a control group; 3 weeks later, these differences were no longer reliable. Time-series analyses revealed that gray matter in the primary motor cortices expanded during the first 4 weeks and then partially renormalized, in particular in the right hemisphere, despite continued practice and increasing task proficiency. Similar patterns of expansion followed by partial renormalization are also found in synaptogenesis, cortical map plasticity, and maturation, and may qualify as a general principle of structural plasticity. Research on human brain plasticity needs to encompass more than 2 measurement occasions to capture expansion and potential renormalization processes over time. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  15. Effect of time to operation on mortality for hypotensive patients with gunshot wounds to the torso: The golden 10 minutes.

    Science.gov (United States)

    Meizoso, Jonathan P; Ray, Juliet J; Karcutskie, Charles A; Allen, Casey J; Zakrison, Tanya L; Pust, Gerd D; Koru-Sengul, Tulay; Ginzburg, Enrique; Pizano, Louis R; Schulman, Carl I; Livingstone, Alan S; Proctor, Kenneth G; Namias, Nicholas

    2016-10-01

    Timely hemorrhage control is paramount in trauma; however, a critical time interval from emergency department arrival to operation for hypotensive gunshot wound (GSW) victims is not established. We hypothesize that delaying surgery for more than 10 minutes from arrival increases all-cause mortality in hypotensive patients with GSW. Data of adults (n = 309) with hypotension and GSW to the torso requiring immediate operation from January 2004 to September 2013 were retrospectively reviewed. Patients with resuscitative thoracotomies, traumatic brain injury, transfer from outside institutions, and operations occurring more than 1 hour after arrival were excluded. Survival analysis using multivariate Cox regression models was used for comparison. Hazard ratios (HRs) and 95% confidence intervals (CIs) are reported. Statistical significance was considered at p ≤ 0.05. The study population was aged 32 ± 12 years, 92% were male, Injury Severity Score was 24 ± 15, systolic blood pressure was 81 ± 29 mm Hg, Glasgow Coma Scale score was 13 ± 4. Overall mortality was 27%. Mean time to operation was 19 ± 13 minutes. After controlling for organ injury, patients who arrived to the operating room after 10 minutes had a higher likelihood of mortality compared with those who arrived in 10 minutes or less (HR, 1.89; 95% CI, 1.10-3.26; p = 0.02); this was also true in the severely hypotensive patients with systolic blood pressure of 70 mm Hg or less (HR, 2.67; 95% CI, 0.97-7.34; p = 0.05). The time associated with a 50% cumulative mortality was 16 minutes. Delay to the operating room of more than 10 minutes increases the risk of mortality by almost threefold in hypotensive patients with GSW. Protocols should be designed to shorten time in the emergency department. Further prospective observational studies are required to validate these findings. Therapeutic study, level IV.

  16. Improved retrieval of land ice topography from CryoSat-2 data and its impact for volume-change estimation of the Greenland Ice Sheet

    DEFF Research Database (Denmark)

    Nilsson, Johan; Gardner, Alex; Sørensen, Louise Sandberg

    2016-01-01

    of the snow/ice surface with lower sensitivity to changes in near-surface dielectric properties. To demonstrate the utility of the new processing methodology we produce elevations, elevation changes, and total volume changes from CryoSat-2 data for the Greenland Ice Sheet during the period January 2011...... to January 2015. We find that the Greenland Ice Sheet decreased in volume at a rate of 289 ± 20km3 a-1, with high interannual variability and spatial heterogeneity in rates of loss. This rate is 65km3 a-1 more negative than rates determined from ESA's L2 product, highlighting the importance of CryoSat-2...

  17. The effect of short-term isometric training on core/torso stiffness.

    Science.gov (United States)

    Lee, Benjamin; McGill, Stuart

    2017-09-01

    "Core" exercise is a basic part of many physical training regimens with goals ranging from rehabilitation of spine and knee injuries to improving athletic performance. Core stiffness has been proposed to perform several functions including reducing pain by minimising joint micro-movements, and enhancing strength and speed performance. This study probes the links between a training approach and immediate but temporary changes in stiffness. Passive and active stiffness was measured on 24 participants; 12 having little to no experience in core training (inexperienced), and the other 12 being athletes experienced to core training methods; before and after a 15 min bout of isometric core exercises. Passive stiffness was assessed on a "frictionless" bending apparatus and active stiffness assessed via a quick release mechanism. Short-term isometric core training increased passive and active stiffness in most directions for both inexperienced and experienced participants, passive left lateral bend among experienced participants being the exception (P core stiffness, in this case following a single session. This may influence performance and injury resilience for a brief period.

  18. Genetic influences on individual differences in longitudinal changes in global and subcortical brain volumes : Results of the ENIGMA plasticity working group

    NARCIS (Netherlands)

    Brouwer, Rachel M; Panizzon, Matthew S; Glahn, David C; Hibar, Derrek P; Hua, Xue; Jahanshad, Neda; Abramovic, Lucija; De Zubicaray, Greig I; Franz, Carol E; Hansell, Narelle K; Hickie, Ian B; Koenis, Marinka M G; Martin, Nicholas G; Mather, Karen A; McMahon, Katie L; Schnack, Hugo G; Strike, Lachlan T; Swagerman, Suzanne C; Thalamuthu, Anbupalam; Wen, Wei; Gilmore, John H; Gogtay, Nitin; Kahn, René S; Sachdev, Perminder S; Wright, Margaret J; Boomsma, Dorret I; Kremen, William S; Thompson, Paul M; Hulshoff Pol, Hilleke E

    2017-01-01

    Structural brain changes that occur during development and ageing are related to mental health and general cognitive functioning. Individuals differ in the extent to which their brain volumes change over time, but whether these differences can be attributed to differences in their genotypes has not

  19. Resistance training intensity and volume affect changes in rate of force development in resistance-trained men.

    Science.gov (United States)

    Mangine, Gerald T; Hoffman, Jay R; Wang, Ran; Gonzalez, Adam M; Townsend, Jeremy R; Wells, Adam J; Jajtner, Adam R; Beyer, Kyle S; Boone, Carleigh H; Miramonti, Amelia A; LaMonica, Michael B; Fukuda, David H; Ratamess, Nicholas A; Stout, Jeffrey R

    2016-12-01

    To compare the effects of two different resistance training programs, high intensity (INT) and high volume (VOL), on changes in isometric force (FRC), rate of force development (RFD), and barbell velocity during dynamic strength testing. Twenty-nine resistance-trained men were randomly assigned to either the INT (n = 15, 3-5 RM, 3-min rest interval) or VOL (n = 14, 10-12 RM, 1-min rest interval) training group for 8 weeks. All participants completed a 2-week preparatory phase prior to randomization. Measures of barbell velocity, FRC, and RFD were performed before (PRE) and following (POST) the 8-week training program. Barbell velocity was determined during one-repetition maximum (1RM) testing of the squat (SQ) and bench press (BP) exercises. The isometric mid-thigh pull was used to assess FRC and RFD at specific time bands ranging from 0 to 30, 50, 90, 100, 150, 200, and 250 ms. Analysis of covariance revealed significant (p velocity. Results indicate that INT is more advantageous than VOL for improving FRC and RFD, while changes in barbell velocity during dynamic strength testing are similarly improved by both protocols in resistance-trained men.

  20. Camera on Vessel: A Camera-Based System to Measure Change in Water Volume in a Drinking Glass

    Directory of Open Access Journals (Sweden)

    Idowu Ayoola

    2015-09-01

    Full Text Available A major problem related to chronic health is patients’ “compliance” with new lifestyle changes, medical prescriptions, recommendations, or restrictions. Heart-failure and hemodialysis patients are usually placed on fluid restrictions due to their hemodynamic status. A holistic approach to managing fluid imbalance will incorporate the monitoring of salt-water intake, body-fluid retention, and fluid excretion in order to provide effective intervention at an early stage. Such an approach creates a need to develop a smart device that can monitor the drinking activities of the patient. This paper employs an empirical approach to infer the real water level in a conically shapped glass and the volume difference due to changes in water level. The method uses a low-resolution miniaturized camera to obtain images using an Arduino microcontroller. The images are processed in MATLAB. Conventional segmentation techniques (such as a Sobel filter to obtain a binary image are applied to extract the level gradient, and an ellipsoidal fitting helps to estimate the size of the cup. The fitting (using least-squares criterion between derived measurements in pixel and the real measurements shows a low covariance between the estimated measurement and the mean. The correlation between the estimated results to ground truth produced a variation of 3% from the mean.

  1. Early changes of parotid density and volume predict modifications at the end of therapy and intensity of acute xerostomia

    Energy Technology Data Exchange (ETDEWEB)

    Belli, Maria Luisa; Broggi, Sara [Ospedale San Raffaele Scientific Institute, Medical Physics, Milano (Italy); Scalco, Elisa; Rizzo, Giovanna [CNR, Istituto di Bioimmagini e Fisiologia Molecolare, Milano (Italy); Sanguineti, Giuseppe [Regina Elena National Cancer Institute, Department of Radiation Oncology, Rome (Italy); Fiorino, Claudio; Cattaneo, Giovanni Mauro [Ospedale San Raffaele Scientific Institute, Medical Physics, Milano (Italy); CNR, Istituto di Bioimmagini e Fisiologia Molecolare, Milano (Italy); Dinapoli, Nicola; Valentini, Vincenzo [Universita Cattolica del Sacro Cuore, Radiotherapy, Rome (Italy); Ricchetti, Francesco [Ospedale Sacro Cuore, Radiotherapy, Negrar (Italy)

    2014-11-15

    To quantitatively assess the predictive power of early variations of parotid gland volume and density on final changes at the end of therapy and, possibly, on acute xerostomia during IMRT for head-neck cancer. Data of 92 parotids (46 patients) were available. Kinetics of the changes during treatment were described by the daily rate of density (rΔρ) and volume (rΔvol) variation based on weekly diagnostic kVCT images. Correlation between early and final changes was investigated as well as the correlation with prospective toxicity data (CTCAEv3.0) collected weekly during treatment for 24/46 patients. A higher rΔρ was observed during the first compared to last week of treatment (-0,50 vs -0,05HU, p-value = 0.0001). Based on early variations, a good estimation of the final changes may be obtained (Δρ: AUC = 0.82, p = 0.0001; Δvol: AUC = 0.77, p = 0.0001). Both early rΔρ and rΔvol predict a higher ''mean'' acute xerostomia score (≥ median value, 1.57; p-value = 0.01). Median early density rate changes for patients with mean xerostomia score ≥ / < 1.57 were -0.98 vs -0.22 HU/day respectively (p = 0.05). Early density and volume variations accurately predict final changes of parotid glands. A higher longitudinally assessed score of acute xerostomia is well predicted by higher rΔρ and rΔvol in the first two weeks of treatment: best cut-off values were -0.50 HU/day and -380 mm{sup 3}/day for rΔρ and rΔvol respectively. Further studies are necessary to definitively assess the potential of early density/volume changes in identifying more sensitive patients at higher risk of experiencing xerostomia. (orig.) [German] Ziel der Studie ist die Untersuchung der praediktiven Aussagekraft von fruehen Veraenderungen in Volumen und Dichte der Ohrspeicheldruese in Bezug auf die finale Verformung zum Ende der Therapie sowie das Risiko von Xerostomie waehrend der intesitaetsmodulierten Strahlentherapie (IMRT) bei Kopf und Hals Tumoren. Die Studie

  2. 1H-NMR and HPLC studies of the changes involved in volume regulation in the muscle fibres of the crab, Hemigrapsus edwardsi.

    Science.gov (United States)

    Bedford, J J; Smith, R A; Thomas, M; Leader, J P

    1991-01-01

    1. The process of cell volume readjustment, during adaptation to salinity changes, in muscle fibres of the euryhaline New Zealand shore crab, Hemigrapsus edwardsi, involve large changes in the amounts of free amino acid. 2. These are taurine, proline, alanine, arginine, glutamic acid, glycine and serine. 3. These changes may be quantified by High Performance Liquid Chromatography, and qualitatively demonstrated by proton nuclear magnetic resonance spectroscopy.

  3. The influence of peat volume change and vegetation on the hydrology of a kettle-hole wetland in Southern Ontario, Canada

    Directory of Open Access Journals (Sweden)

    P. Whittington

    2007-12-01

    Full Text Available Links between local hydrology and vegetation type exist in wetlands, yet it is unclear what role peat volume change plays in these interactions. We measured peat volume change and hydraulic conductivity (Kfield at three contrasting sites located on the quaking vegetation mat of a kettle-hole peatland in southern Ontario. The three sites had visibly different plant communities and were named, according to their dominant vegetation, Sedge (Carex spp., Typha (Typha angustifolia and Carr (Cornus stolonifera. Peat was also collected for laboratory studies of peat volume change, vertical (Kv and horizontal (Kh hydraulic conductivity and the effect of compression on hydraulic conductivity (Kc.In the field, the water table rose throughout the study period, resulting in swelling of the peat. Peat volume change above the -100 cm layer was 11.2%, 6.0% and 3.8% at the Sedge, Typha, and Carr sites respectively. In laboratory samples, a falling water table caused compression of the peat below the structured surface mat, and relative peat volume change between the sites followed the same pattern as in the field. Kfield, Kv and Kh generally decreased with depth from ca. 10-2 to 10-6 cm s-1. In the surface layers (0 to -50cm K trended Carr>Typha>Sedge, whereas the reverse trend was observed in deeper peat. Artificial compression affected K only in the uppermost layers (0 to -15cm. The decline in Kc with compression also trended Sedge>Typha>Carr. Differences in peat volume change and K are probably related to differences in vegetation and soil structure, and may be important for maintaining suitable growing conditions within each community.

  4. Can radiological changes in lymph node volume during treatment predict success of radiation therapy in patients with locally advanced head and neck squamous cell carcinoma?

    International Nuclear Information System (INIS)

    Mishra, Sanju; Hammond, Alexander; Read, Nancy; Venkatesan, Varagur; Warner, Andrew; Winquist, Eric; Nichols, Anthony

    2013-01-01

    Assessment of nodal response after radiotherapy (RT) for head and neck squamous cell carcinoma is difficult, as both CT and positron emission tomography scanning have limited predictive value for residual disease. We sought to measure changes in nodal volume during RT to determine whether such changes are predictive of nodal disease control. Patients with locally advanced head and neck squamous cell carcinoma treated with 70Gy of radical RT (±chemotherapy or anti-epidermal growth factor receptor (EGFR) antibodies) were eligible. Baseline pre-RT scans and cone-beam CT scans done at the outset of treatment and at weeks 3, 5 and 7 (cone-beam CTs 1, 2, 3 and 4, respectively) were deformably coregistered, and 3D nodal volumes were measured. Thirty-eight eligible patients were identified. The main primary tumour site was oropharyngeal; most patients had stage IVa disease. Twenty-seven patients received concurrent platinum-based chemotherapy, 10 received only an EGFR inhibitor with RT and one received RT alone. Twelve patients had a failure in the neck. After week 1 of treatment, a 4% mean decrease in nodal volume was observed, increasing to 40% at week 7. Platinum-based chemotherapy achieved significantly greater decreases in nodal volume than EGFR inhibitors (44 vs. 25%; P=0.026). Advanced tumour stage predicted neck failure (P=0.002), but nodal volumes did not correlate with neck control. Changes in nodal volume are minimal initially during RT but accelerate during the latter weeks of therapy. This study suggests that chemotherapy achieves a greater decrease in nodal volume than EGFR inhibitors and that nodal changes do not predict disease control in the neck.

  5. Effects of balance ability and handgrip height on kinematics of the gait, torso, and pelvis in elderly women using a four-wheeled walker.

    Science.gov (United States)

    Choi, Hyuk-Jae; Ko, Chang-Yong; Kang, Sungjae; Ryu, Jeicheong; Mun, Museong; Jeon, Hye-Seon

    2015-02-01

    Numerous elderly individuals use the four-wheeled walker (FWW) as a gait-assistive device. The walker's handgrip height is important for correct use. However, few clinical studies have investigated the biomechanical effects of the FWW's handgrip height on balance. Therefore, the present study assessed kinematic features of the gait, torso and pelvis during use of the FWW at two levels of handgrip height (48% vs 55% of the subject's height) while assessing balance in older adults. A total of 20 older adults were allocated into two groups according to the Berg Balance Scale (BBS): good balance (GB; BBS≥46) versus poor balance (PB; BBS<45). Participants walked with the FWW at 48% or 55% handgrip height for 10 m. Our study showed that the double-support period and stance phase significantly increased at 55% handgrip height, but the swing phase significantly decreased in the GB group. In the PB group, velocity and stride length significantly increased at 55% handgrip height. Tilt angle of the torso in the GB group was significantly lower at 55% than at 48% handgrip height, but no differences were observed in the PB group. In the pelvis, initial contact and toe-off angles of tilt were lower in the GB group at 55% handgrip height, but no differences were observed in the PB group. These results showed that kinematic features of the gait, torso, and pelvis in older adults using the FWW might be dependent on the handgrip height of the FWW and the patient's balance. Additionally, greater than 48% of the body height might be appropriate for older adults with poor balance. © 2014 Japan Geriatrics Society.

  6. Automated segmentation and recognition of abdominal wall muscles in X-ray torso CT images and its application in abdominal CAD

    International Nuclear Information System (INIS)

    Zhou, X.; Kamiya, N.; Hara, T.; Fujita, H.; Chen, H.; Yokoyama, R.; Hoshi, H.

    2007-01-01

    The information of abdominal wall is very important for the planning of surgical operation and abdominal organ recognition. In research fields of computer assisted radiology and surgery and computer-aided diagnosis, the segmentation and recognition of the abdominal wall muscles in CT images is a necessary pre-processing step. Due to the complexity of the abdominal wall structure and indistinctive in CT images, the automated segmentation of abdominal wall muscles is a difficult issue and has not been solved completely. We propose an approach to segment the abdominal wall muscles and divide it into three categories (front abdominal muscles including rectus abdominis; left and right side abdominal muscles including external oblique, internal oblique and transversus abdominis muscles) automatically. The approach, first, makes an initial classification of bone, fat, and muscles and organs based on the CT number. Then a layer structure is generated to describe the 3-D anatomical structures of human torso by stretching the torso region onto a thin-plate for easy recognition. The abdominal wall muscles are recognized on the layer structures using the spatial relations to the skeletal structure and CT numbers. Finally, the recognized regions are mapped back to the 3-D CT images using an inverse transformation of the stretching process. This method is applied to 20 cases of torso CT images and evaluations are based on visual comparison of the recognition results and the original CT images by an expert in anatomy. The results show that our approach can segment and recognize abdominal wall muscle regions effectively. (orig.)

  7. Changes of the liver volume and the Child-Pugh score after high dose hypofractionated radiotherapy in patients with small hepatocellular carcinoma

    International Nuclear Information System (INIS)

    Kim, Young Il; Park, Hee Chul; Lim, Do Hoon; Park, Hyo Jung; Park, Su Yeon; Kim, Jin Sung; Han, Young Yih; Kang, Sang Won; Paik, Seung Woon

    2012-01-01

    To investigate the safety of high dose hypofractionated radiotherapy (RT) in patients with small hepatocellular carcinoma (HCC) in terms of liver volumetric changes and clinical liver function. We retrospectively reviewed 16 patients with small HCC who were treated with high dose hypofractionated RT between 2006 and 2009. The serial changes of the liver volumetric parameter were analyzed from pre-RT and follow-up (FU) computed tomography (CT) scans. We estimated linear time trends of whole liver volume using a linear mixed model. The serial changes of the Child-Pugh (CP) scores were also analyzed in relation to the volumetric changes. Mean pre-RT volume of entire liver was 1,192.2 mL (range, 502.6 to 1,310.2 mL) and mean clinical target volume was 14.7 mL (range, 1.56 to 70.07 mL). Fourteen (87.5%) patients had 4 FU CT sets and 2 (12.5%) patients had 3 FU CT sets. Mean interval between FU CT acquisition was 2.5 months. After considering age, gender and the irradiated liver volume as a fixed effects, the mixed model analysis confirmed that the change in liver volume is not significant throughout the time course of FU periods. Majority of patients had a CP score change less than 2 except in 1 patient who had CP score change more than 3. The high dose hypofractionated RT for small HCC is relatively safe and feasible in terms of liver volumetric changes and clinical liver function.

  8. Possible interrelationship between changes in F-actin and myosin II, protein phosphorylation, and cell volume regulation in Ehrlich ascites tumor cells

    DEFF Research Database (Denmark)

    Pedersen, S F; Hoffmann, E K

    2002-01-01

    effects on F-actin. The subsequent F-actin depolymerization, however, appeared MLCK- and PKC-dependent, and the initial swelling-induced F-actin depolymerization was MLCK-dependent; both effects were apparently secondary to kinase-mediated effects on cell volume changes. NHE1 in EATC is activated both....... Moreover, Rho kinase inhibition did not significantly affect NHE1 activation, neither by shrinkage nor by CL-A. Implications for the possible interrelationship between changes in F-actin and myosin II, protein phosphorylation, and cell volume regulation are discussed....

  9. Changes in the electro-physical properties of MCT epitaxial films affected by a plasma volume discharge induced by an avalanche beam in atmospheric-pressure air

    Science.gov (United States)

    Grigoryev, D. V.; Voitsekhovskii, A. V.; Lozovoy, K. A.; Tarasenko, V. F.; Shulepov, M. A.

    2015-11-01

    In this paper the influence of the plasma volume discharge of nanosecond duration formed in a non-uniform electric field at atmospheric pressure on samples of epitaxial films HgCdTe (MCT) films are discussed. The experimental data show that the action of pulses of nanosecond volume discharge in air at atmospheric pressure leads to changes in the electrophysical properties of MCT epitaxial films due to formation of a near-surface high- conductivity layer of the n-type conduction. The preliminary results show that it is possible to use such actions in the development of technologies for the controlled change of the properties of MCT.

  10. Hypofractionated stereotactic radiotherapy of acoustic neuroma. Volume changes and hearing results after 89-month median follow-up

    Energy Technology Data Exchange (ETDEWEB)

    Kranzinger, Manfred; Fastner, Gerd [Paracelsus Medical University Clinics (PMU), University Clinic of Radiotherapy and Radio-Oncology, Salzburg County Hospital, Salzburg (Austria); Zehentmayr, Franz; Sedlmayer, Felix [Paracelsus Medical University Clinics (PMU), University Clinic of Radiotherapy and Radio-Oncology, Salzburg County Hospital, Salzburg (Austria); Salzburg County Hospital, Paracelsus Medical University Clinics, radART - Institute for Research and Development on Advanced Radiation Technologies, Salzburg (Austria); Oberascher, Gerhard [Paracelsus Medical University Clinics (PMU), University Clinic of Ear, Nose and Throat Diseases, Salzburg County Hospital, Salzburg (Austria); Merz, Florian; Rahim, Hassan [Salzburg County Hospital, Paracelsus Medical University Clinics, Medical Radiation Protection Unit, Salzburg (Austria); Nairz, Olaf [Clinic Bad Trissl, Oberaudorf (Germany)

    2014-09-15

    The goal of this work was to evaluate toxicity and local control following hypofractionated stereotactic radiation treatment with special focus on changes in tumor volume and hearing capacity. In all, 29 patients with unilateral acoustic neuroma were treated between 2001 and 2007 within a prospective radiation protocol (7 x 4 Gy ICRU dose). Median tumor volume was 0.9 ml. Follow-up started at 6 months and was repeated annually with MRI volumetry and audiometry. Hearing preservation was defined as preservation of Class A/B hearing according to the guidelines of the American Academy of Otolaryngology (1995). No patient had any intervention after a median imaging follow-up of 89.5 months, one patient showed radiological progression. Transient increase of tumor volume developed in 17/29 patients, whereas 22/29 patients (75.9 %) presented with a volume reduction at last follow-up. A total of 21 patients were eligible for hearing evaluation. Mean pure tone average (PTA) deteriorated from 39.3 to 65.9 dB and mean speech discrimination score (SDS) dropped from 74.3 to 38.1 %. The 5-year actuarial Class A/B hearing preservation rate was 50.0 ± 14.4 %. Radiation increases only minimally, if at all, the hearing deterioration which emerges by observation alone. Presbyacusis is not responsible for this deterioration. Transient tumor enlargement is common. Today radiation of small- and medium-sized acoustic neuroma can be performed with different highly conformal techniques as fractionated treatment or single low-dose radiosurgery with equal results regarding tumor control, hearing preservation, and side effects. Hypofractionation is more comfortable for the patient than conventional regimens and represents a serious alternative to frameless radiosurgery. (orig.) [German] Ziel der Studie war die Evaluierung der Toxizitaet und der lokalen Tumorkontrolle einer hypofraktionierten stereotaktischen Bestrahlung mit besonderem Augenmerk auf Veraenderungen von Tumorvolumen und

  11. The influence of whole-body vs. torso pre-cooling on physiological strain and performance of high-intensity exercise in the heat.

    Science.gov (United States)

    Sleivert, G G; Cotter, J D; Roberts, W S; Febbraio, M A

    2001-04-01

    Little research has been reported examining the effects of pre-cooling on high-intensity exercise performance, particularly when combined with strategies to keep the working muscle warm. This study used nine active males to determine the effects of pre-cooling the torso and thighs (LC), pre-cooling the torso (ice-vest in 3 degrees C air) while keeping the thighs warm (LW), or no cooling (CON: 31 degrees C air), on physiological strain and high-intensity (45-s) exercise performance (33 degrees C, 60% rh). Furthermore, we sought to determine whether performance after pre-cooling was influenced by a short exercise warm-up. The 45-s test was performed at different (PForearm blood flow prior to exercise was also lower in LC (3.1+/-2.0 ml 100 ml tissue(-1) x min(-1)) than CON (8.2+/-2.5, P=0.01) but not LW (4.3+/-2.6, P=0.46). After an exercise warm-up, muscle temperature (Tm) was not significantly different between conditions (CON: 37.3+/-1.5, LW: 37.3+/-1.2, LC: 36.6+/-0.7 degrees C, P=0.16) but when warm-up was excluded, T(m) was lower in LC (34.5+/-1.9 degrees C, P=0.02) than in CON (37.3+/-1.0) and LW (37.1+/-0.9). Even when a warm-up was performed, torso+thigh pre-cooling decreased both peak (-3.4+/-3.8%, P=0.04) and mean power output (-4.1+/-3.8%, P=0.01) relative to the control, but this effect was markedly larger when warm-up was excluded (peak power -7.7+/-2.5%, P=0.01; mean power -7.6+/-1.2%, P=0.01). Torso-only pre-cooling did not reduce peak or mean power, either with or without warm-up. These data indicate that pre-cooling does not improve 45-s high-intensity exercise performance, and can impair performance if the working muscles are cooled. A short exercise warm-up largely removes any detrimental effects of a cold muscle on performance by increasing Tm.

  12. The four-dimensional non-uniform rational B-splines-based cardiac-torso phantom and its application in medical imaging research

    International Nuclear Information System (INIS)

    Li Chongguo; Wu Dake; Lang Jinyi

    2008-01-01

    Simulation skill is playing an increasingly important role in medical imaging research. four-dimensional non-uniform rational B-splines-based cardiac-torso (4D NCAT) phantom is new tool for meoical imaging res catch and when combined with accurate models for the imaging process a wealth of realistic imaging data from subjects of various anatomies. Can be provided 4D NCAT phantoms have bend widely used in medical research such as SPECT, PET, CT and so on. 4D NCAT phantoms have also been used in inverse planning system of intensity modulated radiation therapy. (authors)

  13. Changes in synovial membrane and joint effusion volumes after intraarticular methylprednisolone. Quantitative assessment of inflammatory and destructive changes in arthritis by MRI

    DEFF Research Database (Denmark)

    Østergaard, Mikkel; Stoltenberg, M; Gideon, P

    1996-01-01

    OBJECTIVE: To evaluate synovial membrane volumes, effusion volumes, and cartilage and bone erosion scores determined by magnetic resonance imaging (MRI) as markers of disease activity and severity in arthritis. METHODS: Gadolinium-DTPA enhanced MRI of 18 arthritic knees was performed before and 1......, 7, 30 and 180 days after intraarticular methylprednisolone injection until clinical relapse. Intraobserver, interobserver, and inter-MRI variations were determined from 2 successive MRI of another 6 knees. RESULTS: In all knees synovial membrane and effusion volumes decreased within the first...... posttreatment week (median decrease 49 and 65%, respectively), and remained low during remission. Synovial volumes, but not effusion volumes, increased to pretreatment levels in case of clinical relapse, indicating that synovial volumes were most important to the clinical appearance. The intraobserver...

  14. Changes in Prostate Shape and Volume and Their Implications for Radiotherapy After Introduction of Endorectal Balloon as Determined by MRI at 3T

    International Nuclear Information System (INIS)

    Heijmink, Stijn W.T.P.J.; Scheenen, Tom W.J.; Lin, Emile N.J.T. van; Visser, Andries G.; Kiemeney, Lambertus A.L.M.; Witjes, J. Alfred; Barentsz, Jelle O.

    2009-01-01

    Purpose: To determine the changes in prostate shape and volume after the introduction of an endorectal coil (ERC) by means of magnetic resonance imaging (MRI) at 3T. Methods and materials: A total of 44 consecutive patients with biopsy-proven prostate cancer underwent separate MRI examinations at 3T with a body array coil and subsequently with an ERC inflated with 50 mL of fluid. Prospectively, two experienced readers independently evaluated all data sets in random order. The maximal anteroposterior, right-to-left, and craniocaudal prostate diameters, as well as the total prostate and peripheral zone and central gland volumes were measured before and after ERC introduction. The changes in prostate shape and volume were analyzed using Wilcoxon's test for paired samples. Results: The introduction of the ERC significantly changed the prostate shape in all three directions, with mean changes in the anteroposterior, right-to-left, and craniocaudal diameters of 15.7% (5.5 mm), 7.7% (3.5 mm), and 6.3% (2.2 mm), respectively. The mean total prostate, peripheral zone, and central gland volume decreased significantly after ERC introduction by 17.9% (8.3 cm 3 ), 21.6% (4.8 cm 3 ), and 14.2% (3.4 cm 3 ), respectively. Conclusion: ERC introduction as observed by 3T MRI changed the prostate shape and volume significantly. The mean anteroposterior diameter was reduced by nearly one-sixth of its original diameter, and the mean total prostate volume was decreased by approximately 18%. This could cause difficulties and should be considered when using ERC-based MRI for MRI-computed tomography fusion and radiotherapy planning.

  15. Hemodynamic and radionuclide effects of acute captopril therapy for heart failure: changes in left and right ventricular volumes and function at rest and during exercise

    International Nuclear Information System (INIS)

    Massie, B.; Kramer, B.L.; Topic, N.; Henderson, S.G.

    1982-01-01

    Although the resting hemodynamic effects of captopril in congestive heart failure are known, little information is available about the hemodynamic response to captopril during exercise or about changes in noninvasive measurements of the size and function of both ventricles. In this study, 14 stable New York Heart Association class III patients were given 25 mg of oral captopril. Rest and exercise hemodynamic measurements and blood pool scintigrams were performed simultaneously before and 90 minutes after captopril. The radionuclide studies were analyzed for left and right ventricular end-diastolic volumes, end-systolic volumes, ejection fractions and pulmonary blood volume. The primary beneficial responses at rest were decreases in left and right ventricular end-diastolic volumes from 388 +/- 81 to 350 +/- 77 ml and from 52 +/- 26 to 43 +/- 20 volume units, respectively, and in their corresponding filling pressures, from 24 +/- 10 to 17 +/- 9 mm Hg and 10 +/- 5 to 6 +/- 5 mm Hg. Although stroke volume did not increase significantly, both left and right ventricular ejection fractions increased slightly, from 19 +/- 6% to 22+/- 5% and from 25 +/- 9% to 29 +/- 11%, respectively. During exercise, similar changes were noted in both hemodynamic and radionuclide indexes. This, in patients with moderate symptomatic limitation from chronic heart failure, captopril predominantly reduces ventricular volume and filling pressure, with a less significant effect on cardiac output. These effects persist during exercise, when systemic vascular resistance is already very low. Radionuclide techniques are valuable in assessing the drug effect in these subjects, particularly when ventricular volumes are also measured

  16. Changes in synovial membrane and joint effusion volumes after intraarticular methylprednisolone. Quantitative assessment of inflammatory and destructive changes in arthritis by MRI

    DEFF Research Database (Denmark)

    Østergaard, Mikkel; Stoltenberg, M; Gideon, P

    1996-01-01

    OBJECTIVE: To evaluate synovial membrane volumes, effusion volumes, and cartilage and bone erosion scores determined by magnetic resonance imaging (MRI) as markers of disease activity and severity in arthritis. METHODS: Gadolinium-DTPA enhanced MRI of 18 arthritic knees was performed before and 1...

  17. Changes in prostate shape and volume and their implications for radiotherapy after introduction of endorectal balloon as determined by MRI at 3T.

    NARCIS (Netherlands)

    Heijmink, S.W.T.P.J.; Scheenen, T.W.J.; Lin, E.N.J.T. van; Visser, A.G.; Kiemeney, L.A.L.M.; Witjes, J.A.; Barentsz, J.O.

    2009-01-01

    PURPOSE: To determine the changes in prostate shape and volume after the introduction of an endorectal coil (ERC) by means of magnetic resonance imaging (MRI) at 3T. METHODS AND MATERIALS: A total of 44 consecutive patients with biopsy-proven prostate cancer underwent separate MRI examinations at 3T

  18. Hippocampal volume change measurement: Quantitative assessment of the reproducibility of expert manual outlining and the automated methods FreeSurfer and FIRST

    NARCIS (Netherlands)

    Mulder, E.R.; de Jong, R.A.; Knol, D.L.; van Schijndel, R.A.; Cover, K.S.; Visser, P.J.; Barkhof, F.; Vrenken, H.

    2014-01-01

    Background: To measure hippocampal volume change in Alzheimer's disease (AD) or mild cognitive impairment (MCI), expert manual delineation is often used because of its supposed accuracy. It has been suggested that expert outlining yields poorer reproducibility as compared to automated methods, but

  19. A new method to study changes in microvascular blood volume in muscle and adipose tissue: Real time imaging in humans and rat

    DEFF Research Database (Denmark)

    Sjøberg, Kim Anker; Rattigan, Stephen; Hiscock, Natalie J

    2011-01-01

    We employed and evaluated a new application of contrast enhanced ultrasound for real time imaging of changes in microvascular blood volume (MVB) in tissues in females, males and rat. Continuous real time imaging was performed using contrast enhanced ultrasound to quantify infused gas filled micro...

  20. Blood-retinal barrier glycerol permeability in diabetic macular edema and healthy eyes: estimations from macular volume changes after peroral glycerol

    DEFF Research Database (Denmark)

    Thornit, Dorte Nellemann; Vinten, Carl Martin; Sander, Birgit

    2010-01-01

    PURPOSE: To compare the changes in macular volume (MV) between healthy subjects and patients with diabetic macular edema (DME) after an osmotic load and to determine the glycerol permeability (P(gly)) of the blood-retinal barrier (BRB). METHODS: In this unmasked study, 13 patients with DME and 5...

  1. A newly developed maneuver, field change conversion (FCC), improved evaluation of the left ventricular volume more accurately on quantitative gated SPECT (QGS) analysis

    International Nuclear Information System (INIS)

    Tajima, Osamu; Shibasaki, Masaki; Hoshi, Toshiko; Imai, Kamon

    2002-01-01

    The purpose of this study was to investigate whether a newly developed maneuver that reduces the reconstruction area by a half more accurately evaluates left ventricular (LV) volume on quantitative gated SPECT (QGS) analysis. The subjects were 38 patients who underwent left ventricular angiography (LVG) followed by G-SPECT within 2 weeks. Acquisition was performed with a general purpose collimator and a 64 x 64 matrix. On QGS analysis, the field magnification was 34 cm in original image (Original: ORI), and furthermore it was changed from 34 cm to 17 cm to enlarge the re-constructed image (Field Change Conversion: FCC). End-diastolic volume (EDV) and end-systolic volume (ESV) of the left ventricle were also obtained using LVG. EDV was 71±19 ml, 83±20 ml and 98±23 ml for ORI, FCC and LVG, respectively (p<0.001: ORI versus LVG, p<0.001: ORI versus FCC, p<0.001: FCC versus LVG). ESV was 28±12 ml, 34±13 ml and 41±14 ml for ORI, FCC and LVG, respectively (p<0.001: ORI versus LVG, p<0.001: ORI versus FCC, p<0.001: FCC versus LVG). FCC was better than ORI for calculating LV volume in clinical cases. Furthermore, FCC is a useful method for accurately measuring the LV volume on QGS analysis. (author)

  2. Relationships of peripheral IGF-1, VEGF and BDNF levels to exercise-related changes in memory, hippocampal perfusion and volumes in older adults.

    Science.gov (United States)

    Maass, Anne; Düzel, Sandra; Brigadski, Tanja; Goerke, Monique; Becke, Andreas; Sobieray, Uwe; Neumann, Katja; Lövdén, Martin; Lindenberger, Ulman; Bäckman, Lars; Braun-Dullaeus, Rüdiger; Ahrens, Dörte; Heinze, Hans-Jochen; Müller, Notger G; Lessmann, Volkmar; Sendtner, Michael; Düzel, Emrah

    2016-05-01

    Animal models point towards a key role of brain-derived neurotrophic factor (BDNF), insulin-like growth factor-I (IGF-I) and vascular endothelial growth factor (VEGF) in mediating exercise-induced structural and functional changes in the hippocampus. Recently, also platelet derived growth factor-C (PDGF-C) has been shown to promote blood vessel growth and neuronal survival. Moreover, reductions of these neurotrophic and angiogenic factors in old age have been related to hippocampal atrophy, decreased vascularization and cognitive decline. In a 3-month aerobic exercise study, forty healthy older humans (60 to 77years) were pseudo-randomly assigned to either an aerobic exercise group (indoor treadmill, n=21) or to a control group (indoor progressive-muscle relaxation/stretching, n=19). As reported recently, we found evidence for fitness-related perfusion changes of the aged human hippocampus that were closely linked to changes in episodic memory function. Here, we test whether peripheral levels of BDNF, IGF-I, VEGF or PDGF-C are related to changes in hippocampal blood flow, volume and memory performance. Growth factor levels were not significantly affected by exercise, and their changes were not related to changes in fitness or perfusion. However, changes in IGF-I levels were positively correlated with hippocampal volume changes (derived by manual volumetry and voxel-based morphometry) and late verbal recall performance, a relationship that seemed to be independent of fitness, perfusion or their changes over time. These preliminary findings link IGF-I levels to hippocampal volume changes and putatively hippocampus-dependent memory changes that seem to occur over time independently of exercise. We discuss methodological shortcomings of our study and potential differences in the temporal dynamics of how IGF-1, VEGF and BDNF may be affected by exercise and to what extent these differences may have led to the negative findings reported here. Copyright © 2015 The Authors

  3. Radiation-induced parotid gland changes in oral cancer patients. Correlation between parotid volume and saliva production

    International Nuclear Information System (INIS)

    Teshima, Keiko; Murakami, Ryuji; Tomitaka, Etsuji

    2010-01-01

    The objective of this study was to evaluate whether saliva production reflects the parotid volume during the course of radiation therapy (RT) in patients with head-and-neck cancer. Twenty patients with advanced oral squamous cell carcinomas, who were treated with preoperative chemo-RT, underwent morphological assessment with CT or MRI and functional assessment with the Saxon test. For the Saxon test, saliva production was measured by weighing a gauze pad before and 2 min after chewing without swallowing; the low-normal value is 2 g. Saliva production and parotid volumes before and 2 weeks after RT were compared with the paired t-test, the Spearman rank correlation test and the Fisher exact test. After 30 Gy irradiation, mean saliva production was decreased from 4.2 to 1.0 g (P 3 (P<0.01); the post-RT: pre-RT parotid volume ratio ranged from 54% to 85% (mean 71%). Although the initial parotid volume was correlated with initial saliva production (r=0.47, P=0.04), no significant correlation was noted after RT (r=0.08, P=0.71), and there were considerable individual variations. The parotid volume ratio was inversely correlated with the saliva-reduction amount (r=-0.79, P<0.01). There was a correlation between decreased parotid gland volume and decreased saliva production in patients with head-and-neck cancer undergoing RT. Parotid volume reduction may predict parotid gland function. (author)

  4. Hippocampal volume change measurement: quantitative assessment of the reproducibility of expert manual outlining and the automated methods FreeSurfer and FIRST.

    Science.gov (United States)

    Mulder, Emma R; de Jong, Remko A; Knol, Dirk L; van Schijndel, Ronald A; Cover, Keith S; Visser, Pieter J; Barkhof, Frederik; Vrenken, Hugo

    2014-05-15

    To measure hippocampal volume change in Alzheimer's disease (AD) or mild cognitive impairment (MCI), expert manual delineation is often used because of its supposed accuracy. It has been suggested that expert outlining yields poorer reproducibility as compared to automated methods, but this has not been investigated. To determine the reproducibilities of expert manual outlining and two common automated methods for measuring hippocampal atrophy rates in healthy aging, MCI and AD. From the Alzheimer's Disease Neuroimaging Initiative (ADNI), 80 subjects were selected: 20 patients with AD, 40 patients with mild cognitive impairment (MCI) and 20 healthy controls (HCs). Left and right hippocampal volume change between baseline and month-12 visit was assessed by using expert manual delineation, and by the automated software packages FreeSurfer (longitudinal processing stream) and FIRST. To assess reproducibility of the measured hippocampal volume change, both back-to-back (BTB) MPRAGE scans available for each visit were analyzed. Hippocampal volume change was expressed in μL, and as a percentage of baseline volume. Reproducibility of the 1-year hippocampal volume change was estimated from the BTB measurements by using linear mixed model to calculate the limits of agreement (LoA) of each method, reflecting its measurement uncertainty. Using the delta method, approximate p-values were calculated for the pairwise comparisons between methods. Statistical analyses were performed both with inclusion and exclusion of visibly incorrect segmentations. Visibly incorrect automated segmentation in either one or both scans of a longitudinal scan pair occurred in 7.5% of the hippocampi for FreeSurfer and in 6.9% of the hippocampi for FIRST. After excluding these failed cases, reproducibility analysis for 1-year percentage volume change yielded LoA of ±7.2% for FreeSurfer, ±9.7% for expert manual delineation, and ±10.0% for FIRST. Methods ranked the same for reproducibility of 1

  5. Impact of endobronchial coiling on segmental bronchial lumen in treated and untreated lung lobes: Correlation with changes in lung volume, clinical and pulmonary function tests.

    Science.gov (United States)

    Kloth, C; Thaiss, W M; Hetzel, J; Ditt, H; Grosse, U; Nikolaou, K; Horger, M

    2016-07-01

    To assess the impact of endobronchial coiling on the segment bronchus cross-sectional area and volumes in patients with lung emphysema using quantitative chest-CT measurements. Thirty patients (female = 15; median age = 65.36 years) received chest-CT before and after endobronchial coiling for lung volume reduction (LVR) between January 2010 and December 2014. Thin-slice (0.6 mm) non-enhanced image data sets were acquired both at end-inspiration and end-expiration using helical technique and 120 kV/100-150 mAs. Clinical response was defined as an increase in the walking distance (Six-minute walk test; 6MWT) after LVR-therapy. Additionally, pulmonary function test (PFT) measurements were used for clinical correlation. In the treated segmental bronchia, the cross-sectional lumen area showed significant reduction (p  0.05). In the ipsilateral lobes, the lumina showed no significant changes. In the contralateral lung, we found tendency towards increased cross-sectional area in inspiration (p = 0.06). Volumes of the treated segments correlated with the treated segmental bronchial lumina in expiration (r = 0.80, p volume of the treated lobe in responders only. Endobronchial coiling causes significant decrease in the cross-sectional area of treated segment bronchi in inspiration and a slight increase in expiration accompanied by a volume reduction. • Endobronchial coiling has indirect impact on cross-sectional area of treated segment bronchi • Volume changes of treated lobes correlate with changes in bronchial cross-sectional area • Coil-induced effects reflect their stabilizing and stiffening impact on lung parenchyma • Endobronchial coiling reduces bronchial collapsing compensating the loss of elasticity.

  6. Diastolic compliance and exercise-induced left ventricular diastolic volume changes in patients with coronary artery disease

    International Nuclear Information System (INIS)

    Choi, W.; Varma, V.; Wasserman, A.; Katz, R.; Reba, R.; Ross, A.

    1983-01-01

    This study consists of 46 consecutive patients who had supine resting and exercise multigated (MUGA) blood pool studies. All patients had angio-graphically important coronary stenosis in at least one major vessel. Thirty-five out of 46 patients with coronary artery disease increased left ventricular end diastolic volume with a supine exercise. The remaining eleven patients dit not dilate the left ventricle. Those patients, who were able to increase their end diastolic volume during exercise, had better compliance of the left ventricle manifested by lower end diastolic pressures, whereas, patients with poor left ventricular compliance were unable to volume expand during supine exercise

  7. Quantification of serial changes in cerebral blood volume and metabolism in patients with recurrent glioblastoma undergoing antiangiogenic therapy

    Energy Technology Data Exchange (ETDEWEB)

    Stadlbauer, Andreas, E-mail: andi@nmr.at [Institute of Medical Radiology, University Clinic of St. Pölten, Propst Führer-Straße 4, A-3100 St. Pölten (Austria); Department of Neurosurgery, University of Erlangen-Nuremberg, Schwabachanlage 6, D-91054 Erlangen (Germany); Department of Radiology and Nuclear Medicine, Medical University Vienna, Währinger Gürtel 18-20, A-1097 Vienna (Austria); Pichler, Petra [First Department of Internal Medicine, University Clinic of St. Pölten, Propst Führer-Straße 4, A-3100 St. Poelten (Austria); Karl, Marianne [Institute of Medical Radiology, University Clinic of St. Pölten, Propst Führer-Straße 4, A-3100 St. Pölten (Austria); Brandner, Sebastian [Department of Neurosurgery, University of Erlangen-Nuremberg, Schwabachanlage 6, D-91054 Erlangen (Germany); Lerch, Claudia [Institute of Medical Radiology, University Clinic of St. Pölten, Propst Führer-Straße 4, A-3100 St. Pölten (Austria); Renner, Bertold [Institute of Experimental and Clinical Pharmacology and Toxicology, University of Erlangen-Nürnberg, Erlangen (Germany); Heinz, Gertraud [Institute of Medical Radiology, University Clinic of St. Pölten, Propst Führer-Straße 4, A-3100 St. Pölten (Austria)

    2015-06-15

    Highlights: • Antiangiogenic therapy can lead to a decreased in CBV in normal brain tissue. • Responding and pseudoresponding lesions to AAT showed a similar CBV decrease. • Cho and NAA allowed for a distinction of responding and pseudoresponding lesions. • Cr ratios are not suited for evaluation of antiangiogenic therapy response. • Responders to AAT may have an increased risk for remote progression of the GBM. - Abstract: Objectives: To evaluate the usefulness of quantitative advanced magnetic resonance imaging (MRI) methods for assessment of antiangiogenic therapy (AAT) response in recurrent glioblastoma multiforme (GBM). Methods: Eighteen patients with recurrent GBM received bevacizumab and 18 patients served as control group. Baseline MRI and two follow-up examinations were acquired every 3–5 months using dynamic susceptibility-weighted contrast (DSC) perfusion MRI and {sup 1}H-MR spectroscopic imaging ({sup 1}H-MRSI). Maps of absolute cerebral blood volume (aCBV) were coregistered with choline (Cho) and N-acetyl-aspartate (NAA) concentrations and compared to usually used relative parameters as well as controls. Results: Perfusion significantly decreased in responding and pseudoresponding GBMs but also in normal appearing brain after AAT onset. Cho and NAA concentrations were superior to Cr-ratios in lesion differentiation and showed a clear gap between responding and pseudoresponding lesions. Responders to AAT exceptionally frequently (6 out of 8 patients) showed remote GBM progression. Conclusions: Quantification of CBV reveals changes in normal brain perfusion due to AAT, which were not described so far. DSC perfusion MRI seems not to be suitable for differentiation between response and pseudoresponse to AAT. However, absolute quantification of brain metabolites may allow for distinction due to a clear gap at 6–9 months after therapy onset.

  8. Radionuclide-determined changes in pulmonary blood volume and thallium lung uptake in patients with coronary artery disease

    International Nuclear Information System (INIS)

    Wilson, R.A.; Okada, R.D.; Boucher, C.A.; Strauss, H.W.; Pohost, G.M.

    1983-01-01

    Exercise-induced increases in radionuclide-determined pulmonary blood volume (PBV) and thallium lung uptake have been described in patients with coronary artery disease (CAD) and have been shown to correlate with transient exercise-induced left ventricular dysfunction. To compare these 2 techniques in the same patients, 74 patients (59 with and 15 without significant CAD) underwent supine bicycle exercise twice on the same day--first for thallium myocardial and lung imaging and then for technetium-99m gated blood pool imaging for the PBV ratio determination. Thallium activity of lung and myocardium was determined to calculate thallium lung/heart ratio. Relative changes in PBV from rest to exercise were expressed as a ratio of pulmonary counts (exercise/rest). Previously reported normal ranges for thallium lung/heart ratio and PBV ratio were used. The PBV ratio and thallium lung/heart ratio were abnormal in 71 and 36%, respectively, of patients with CAD (p less than 0.01). Both ratios were normal in all patients without CAD. Although the resting ejection fractions did not differ significantly in patients with normal versus those with abnormal PBV ratios or thallium lung/heart ratios, abnormal PBV ratios and thallium lung/heart ratios were associated with an exercise-induced decrease in ejection fraction. Propranolol use was significantly higher in patients with abnormal than in those with normal thallium lung/heart ratios (p less than 0.01). No significant difference in propranolol use was present in patients with abnormal or normal PBV ratios. In conclusion: (1) the prevalence of an abnormal thallium lung/heart ratio is less than that of the PBV ratio in patients with CAD; (2) both tests are normal in normal control subjects; (3) propranolol does not cause abnormal results in normal control subjects; however, propranolol may influence lung thallium uptake in patients with CAD; and (4) when both tests are abnormal, there is a high likelihood of multivessel disease

  9. Groundwater-level and storage-volume changes in the Equus Beds aquifer near Wichita, Kansas, predevelopment through January 2015

    Science.gov (United States)

    Whisnant, Joshua A.; Hansen, Cristi V.; Eslick, Patrick J.

    2015-10-01

    Development of the Wichita well field began in the 1940s in the Equus Beds aquifer to provide the city of Wichita, Kansas, a new water-supply source. After development of the Wichita well field began, groundwater levels began to decline. Extensive development of irrigation wells that began in the 1970s also contributed to substantial groundwater-level declines. Groundwater-level declines likely enhance movement of brine from past oil and gas production near Burrton, Kansas, and natural saline water from the Arkansas River into the Wichita well field. Groundwater levels reached a historical minimum in 1993 because of drought conditions, irrigation, and the city of Wichita’s withdrawals from the aquifer. In 1993, the city of Wichita adopted the Integrated Local Water Supply Program to ensure that Wichita’s water needs would be met through the year 2050 and beyond as part of its efforts to manage the part of the Equus Beds aquifer Wichita uses. A key component of the Integrated Local Water Supply Program was the Equus Beds Aquifer Storage and Recovery project. The Aquifer Storage and Recovery project’s goal is to store and eventually recover groundwater and help protect the Equus Beds aquifer from oil-field brine water near Burrton, Kansas, and saline water from the Arkansas River. Since 1940, the U.S. Geological Survey has monitored groundwater levels and storage-volume changes in the Equus Beds aquifer to provide data to the city of Wichita in order to better manage its water supply.

  10. The radiation response of the cervical spinal cord of the pig: Effects of changing the irradiated volume

    International Nuclear Information System (INIS)

    Van den Aardweg, G.J.M.J.; Hopewell, J.W.; Whitehouse, E.M.

    1995-01-01

    An investigation of the field size effect for the cervical spinal cord of the pig after single doses of γ-rays. In this study, clinically relevant volumes of the spinal cord were irradiated. The effects of the local irradiation of different lengths of the spinal cord (2.5 cm, 5.0 cm, and 10.0 cm) have been evaluated in mature pigs (37-43 weeks). Single doses of 25-31 Gy were given using a 60 Co γ-source, at a dose rate of 0.21-0.30 Gy/min. The incidence of radiation-induced paralysis was used as the endpoint. The data were analyzed using probit analysis and a normal tissue complication probability (NTCP)-model. Twenty-five animals out of a total of 53 developed paralysis, with histological evidence of parenchymal and vascular changes in their white matter. The slope of the dose-response curves decreased with the decrease in field size; however, there was no significant difference at the radiation dose associated with a 50% incidence of paralysis (ED 50 ) irrespective of the method of analysis. The ED 50 values ± standard errors (± SE) were 27.02 ± 0.36 Gy, 27.68 ± 0.57 Gy, and 28.28 ± 0.78 Gy for field lengths of 10, 5, and 2.5 cm, respectively. Analysis of the data with a normal tissue complication probability (NCTP) model gave similar results. The latent period of paralysis was 7.5-16.5 weeks with no significant differences between dose and field size. No significant field size-related differences in response were detectable in the cervical spinal cord of mature pigs after single dose irradiations, specifically at a clinically relevant level of effect ( 10 ). 21 refs., 1 fig., 1 tab

  11. The radiation response of the cervical spinal cord of the pig: effects of changing the irradiated volume

    International Nuclear Information System (INIS)

    Aardweg, Gerard J.M.J. van den; Hopewell, John W.; Whitehouse, Elizabeth M.

    1995-01-01

    Purpose: An investigation of the field size effect for the cervical spinal cord of the pig after single doses of γ-rays. In this study, clinically relevant volumes of the spinal cord were irradiated. Methods and Materials: The effects of the local irradiation of different lengths of the spinal cord (2.5 cm, 5.0 cm, and 10.0 cm) have been evaluated in mature pigs (37-43 weeks). Single doses of 25-31 Gy were given using a 60 Co γ-source, at a dose rate of 0.21-0.30 Gy/min. The incidence of radiation-induced paralysis was used as the endpoint. The data were analyzed using probit analysis and a normal tissue complication probability (NTCP)-model. Results: Twenty-five animals out of a total of 53 developed paralysis, with histological evidence of parenchymal and vascular changes in their white matter. The slope of the dose-response curves decreased with the decrease in field size; however, there was no significant difference at the radiation dose associated with a 50% incidence of paralysis (ED 50 ) irrespective of the method of analysis. The ED 50 values ± standard errors (± SE) were 27.02 ± 0.36 Gy, 27.68 ± 0.57 Gy, and 28.28 ± 0.78 Gy for field lengths of 10, 5, and 2.5 cm, respectively. Analysis of the data with a normal tissue complication probability (NCTP) model gave similar results. The latent period for paralysis was 7.5-16.5 weeks with no significant differences between dose and field size. Conclusion: No significant field size-related differences in response were detectable in the cervical spinal cord of mature pigs after single dose irradiations, specifically at a clinically relevant level of effect ( 10 )

  12. Calcium isotope signature: new proxy for net change in bone volume for chronic kidney disease and diabetic rats.

    Science.gov (United States)

    Tanaka, Yu-Ki; Yajima, Nobuyuki; Higuchi, Yusuke; Yamato, Hideyuki; Hirata, Takafumi

    2017-12-01

    Herein, we measure the Ca isotope ratios ( 44 Ca/ 42 Ca and 43 Ca/ 42 Ca) in serum and bone samples collected from rats with chronic kidney disease (CKD) or diabetes mellitus (DM). For the serum samples, the isotope ratios are lower for the CKD (δ 44 Ca/ 42 Ca serum = 0.16 ± 0.11‰; 2SD, n = 6) and the DM (δ 44 Ca/ 42 Ca serum = -0.11 ± 0.25‰; 2SD, n = 7) rats than that for the control rats (δ 44 Ca/ 42 Ca serum = 0.25 ± 0.04‰; 2SD, n = 7). Bone samples from two distinct positions of 20 rats in total, namely, the center and proximal parts of the tibial diaphysis, are subject to Ca isotope analysis. The resulting δ 44 Ca/ 42 Ca values for the bone of the proximal part are about 0.3‰ lower than that for the serum samples from the same rats. The larger isotope fractionations between the serum and bone are consistent with previously reported data for vertebrate animals (e.g., Skulan and DePaolo, 1999), which suggests the preferential incorporation of lighter Ca isotopes through bone formation. For the bones from the control and CKD rats, there were no differences in the δ 44 Ca/ 42 Ca values between the positions of the bone. In contrast, the δ 44 Ca/ 42 Ca values of the bone for the DM rats were different between the positions of the bone. Due to the lower bone turnover rate for the DM rats, the δ 44 Ca/ 42 Ca for the middle of the diaphysis can reflect the Ca isotopes in the bone formed prior to the progression of DM states. Thus, the resulting δ 44 Ca/ 42 Ca values show a clear correlation with bone mineral density (BMD). This can be due to the release of isotopically lighter Ca from the bone to the serum. In the present study, our data demonstrate that the δ 44 Ca/ 42 Ca value for serum can be used as a new biomarker for evaluating changes in bone turnover rate, followed by changes in bone volume.

  13. Volume and Tissue Composition Changes Measured with Dual-Energy X-Ray Absorptiometry in Melanoma-Related Limb Lymphedema

    DEFF Research Database (Denmark)

    Gjorup, Caroline A; Hendel, Helle W; Zerahn, Bo

    2017-01-01

    Abstracts Background: The aim of this cross-sectional study was to investigate the volume, fat mass, and lean mass in both upper and lower limbs measured with dual-energy X-ray absorptiometry (DXA) in melanoma patients with melanoma-related limb lymphedema. METHODS AND RESULTS: Four hundred thirty...... lymphedema was diagnosed on the basis of history and characteristic physical findings on the clinical examination. The inter-limb differences in volume, fat mass, and lean mass measured with DXA were categorized as none/mild, moderate, or severe according to reference values (taking handedness into account......, and the majority of lymphedemas were categorized as mild. The increase in the volume of limbs with lymphedema was primarily due to an increase in fat mass. CONCLUSION: There is a high prevalence of melanoma-related limb lymphedema. The increase in volume in the limb with lymphedema is primarily due to an increase...

  14. Changes in Peak Oxygen Uptake and Plasma Volume in Fit and Unfit Subjects Following Exposure to a Simulation of Microgravity

    National Research Council Canada - National Science Library

    Convertino, Victor

    1997-01-01

    To test the hypothesis that the magnitude of reduction in plasma volume and work capacity following exposure to simulated microgravity is dependent on the initial level of aerobic fitness, peak oxygen uptake (VO2peak...

  15. Changes in lateral dimensions of irradiated volume and their impact on the accuracy of dose delivery during radiotherapy for head and neck cancer

    International Nuclear Information System (INIS)

    Senkus-Konefka, Elzbieta; Naczk, Edmund; Borowska, Ilona; Badzio, Andrzej; Jassem, Jacek

    2006-01-01

    Background and purpose: To assess changes in lateral dimensions of irradiated volume during head and neck cancer radiotherapy and to determine their impact on the accuracy of dose delivery. Patients and methods: Lateral dimensions of irradiated volumes were measured in five predefined points prior to treatment and then bi-weekly. For each measurement, midline dose was calculated and verified using in vivo dosimetry. Early radiation reactions, patient weight changes and the need to modify radiotherapy accessories were also recorded. The study included 33 head and neck cancer patients irradiated using parallel opposed megavoltage fields. Results: Body mass changes during radiotherapy ranged from -18 to +4 kg (median -5). Lateral dimension changes >5 mm (range -37 to +16) occurred in 32 patients (97%). For axis measurements, the degree of lateral dimension changes were correlated with treatment field size (P=0.022) and degree of mucositis (P=0.017). Axis doses calculated for changed dimensions varied from those prescribed by -2.5 to +6% (median +2%). Differences larger than 5% were present in 4.8% of calculations. In 17 patients (52%), radiotherapy accessories had to be modified during treatment. The need to modify radiotherapy accessories correlated with larger treatment portals (P=0.004), more weight loss during treatment (P=0.01) and higher initial N stage (P=0.04). Conclusions: Changes of irradiated volume lateral dimensions during head and neck cancer radiotherapy may lead to considerable dose delivery inaccuracies. Watchful monitoring, corrections to calculated dose when changes observed are significant and radiotherapy accessories modification during the course of treatment are strongly recommended

  16. Predicting Volume and Biomass Change from Multi-Temporal Lidar Sampling and Remeasured Field Inventory Data in Panther Creek Watershed, Oregon, USA

    Directory of Open Access Journals (Sweden)

    Krishna P. Poudel

    2018-01-01

    Full Text Available Using lidar for large-scale forest management can improve operational and management decisions. Using multi-temporal lidar sampling and remeasured field inventory data collected from 78 plots in the Panther Creek Watershed, Oregon, USA, we evaluated the performance of different fixed and mixed models in estimating change in aboveground biomass ( ∆ AGB and cubic volume including top and stump ( ∆ CVTS over a five-year period. Actual values of CVTS and AGB were obtained using newly fitted volume and biomass equations or the equations used by the Pacific Northwest unit of the Forest Inventory and Analysis program. Estimates of change based on fixed and mixed-effect linear models were more accurate than change estimates based on differences in LIDAR-based estimates. This may have been due to the compounding of errors in LIDAR-based estimates over the two time periods. Models used to predict volume and biomass at a given time were, however, more precise than the models used to predict change. Models used to estimate ∆ CVTS were not as accurate as the models employed to estimate ∆ AGB . Final models had cross-validation root mean squared errors as low as 40.90% for ∆ AGB and 54.36% for ∆ CVTS .

  17. cExternal beam radiation results in minimal changes in post void residual urine volumes during the treatment of clinically localized prostate cancer

    International Nuclear Information System (INIS)

    Orio, Peter F III; Merrick, Gregory S; Allen, Zachariah A; Butler, Wayne M; Wallner, Kent E; Kurko, Brian S; Galbreath, Robert W

    2009-01-01

    To evaluate the impact of external beam radiation therapy (XRT) on weekly ultrasound determined post-void residual (PVR) urine volumes in patients with prostate cancer. 125 patients received XRT for clinically localized prostate cancer. XRT was delivered to the prostate only (n = 66) or if the risk of lymph node involvement was greater than 10% to the whole pelvis followed by a prostate boost (n = 59). All patients were irradiated in the prone position in a custom hip-fix mobilization device with an empty bladder and rectum. PVR was obtained at baseline and weekly. Multiple clinical and treatment parameters were evaluated as predictors for weekly PVR changes. The mean patient age was 73.9 years with a mean pre-treatment prostate volume of 53.3 cc, a mean IPSS of 11.3 and a mean baseline PVR of 57.6 cc. During treatment, PVR decreased from baseline in both cohorts with the absolute difference within the limits of accuracy of the bladder scanner. Alpha-blockers did not predict for a lower PVR during treatment. There was no significant difference in mean PVR urine volumes or differences from baseline in either the prostate only or pelvic radiation groups (p = 0.664 and p = 0.458, respectively). Patients with a larger baseline PVR (>40 cc) had a greater reduction in PVR, although the greatest reduction was seen between weeks one and three. Patients with a small PVR (<40 cc) had no demonstrable change throughout treatment. Prostate XRT results in clinically insignificant changes in weekly PVR volumes, suggesting that radiation induced bladder irritation does not substantially influence bladder residual urine volumes

  18. Environmental and ice volume changes based on seismic stratigraphy in Sabrina Coast, East Antarctica: Preliminary results from NBP1402

    Science.gov (United States)

    Gulick, S. P. S.; Fernandez-Vasquez, R. A.; Frederick, B.; Saustrup, S., Sr.; Domack, E. W.; Lavoie, C.; Shevenell, A.; Blankenship, D. D.; Leventer, A.

    2014-12-01

    In 2014, the R/V Nathaniel B. Palmer (NBP1402) sailed to a virtually unexplored continental shelf along the Sabrina Coast, East Antarctica. The shelf contains the sedimentary record of environmental and ice volume changes within the Aurora Subglacial Basin (ASB), which is presently occupied by ~7 m sea level-rise equivalent of ice. We acquired 750 km of high-resolution seismic data proximal to the Reynolds Trough and Moscow University Ice Shelf glacial systems west of the Dalton Ice Tongue using dual 45/45 cu. in. G.I. guns and a 24 ch. streamer with 3.125 m groups providing a vertical resolution of ~3 m simultaneously with CHIRP data. These are the first images of this margin acquired and show a remarkable set of sequence stratigraphic transitions. Crystalline basement is at the seafloor landward and buried seaward with a transition to smoother reflection interface. Reflective sedimentary strata overlie the basement, dip seaward, and are capped by a landward-dipping regional angular unconformity. Above this are a series of transparent seismic facies that, along with the middle to outer shelf seafloor, dip landward towards a shelf-oblique glacial trough. The older, seaward-dipping strata include a deeper series of units that display at least three stratal architectures interpreted to be shelf deltas implying a pre-glacial, fluvial environment within the drainage basin. Above these sequences, the seismic facies transition to surfaces exhibiting significant erosion, small u-shaped valleys, and channel fill sequences, all of which are reminiscent of temperate glacial features. We interpret these sequences as including sub-ice tunnel valleys and grounding zone wedges with interspersed non-glacial to pro-glacial deposits. Increasing glaciogenic facies upsection suggests a gradual fluvial to glacial transition and increasing glacial extent with time. The subsequent transition to ice sheets is marked by erosion to basement landward and the angular unconformity seaward

  19. Is there a correlation between operative results and change in ventricular volume after shunt placement? A study of 60 cases of idiopathic normal-pressure hydrocephalus

    Energy Technology Data Exchange (ETDEWEB)

    Meier, U.; Graewe, A.; Hajdukova, A. [Department of Neurosurgery, Unfallkrankenhaus Berlin, Warener Strasse 7, 12683, Berlin (Germany); Paris, S.; Stockheim, D.; Mutze, S. [Department of Radiology, Unfallkrankenhaus Berlin, Warener Strasse 7, 12683, Berlin (Germany)

    2003-06-01

    In patients with communicating or normal-pressure hydrocephalus, ventricular volume decreases following implantation of differential pressure valves. We implanted hydrostatic (Miethke dual-switch) valves in 60 patients with normal-pressure hydrocephalus (NPH) between September 1997 and December 2001. The patients underwent CT 1 year after operation, and we measured the Evans index. Although 83% of the patients showed no change in ventricular volume as assessed by this index, 72% nevertheless showed good to excellent and 16% satisfactory clinical improvement, while 12% showed no improvement. Moderate or marked reduction in ventricular size was observed in 17%, of whom 40% of these patients showed good to excellent and 20% satisfactory clinical improvement; 40% showed unsatisfactory improvement. The favourable outcome following implantation of a hydrostatic shunt thus did not correlate with decreased ventricular volume 1 year after operation, better outcomes being observed in patients with little or no alteration in ventricular size than in those with a marked decrease. Postoperative change in ventricular volume in NPH thus does not have the same significance as in patients with high-pressure hydrocephalus. (orig.)

  20. Is there a correlation between operative results and change in ventricular volume after shunt placement? A study of 60 cases of idiopathic normal-pressure hydrocephalus

    International Nuclear Information System (INIS)

    Meier, U.; Graewe, A.; Hajdukova, A.; Paris, S.; Stockheim, D.; Mutze, S.

    2003-01-01

    In patients with communicating or normal-pressure hydrocephalus, ventricular volume decreases following implantation of differential pressure valves. We implanted hydrostatic (Miethke dual-switch) valves in 60 patients with normal-pressure hydrocephalus (NPH) between September 1997 and December 2001. The patients underwent CT 1 year after operation, and we measured the Evans index. Although 83% of the patients showed no change in ventricular volume as assessed by this index, 72% nevertheless showed good to excellent and 16% satisfactory clinical improvement, while 12% showed no improvement. Moderate or marked reduction in ventricular size was observed in 17%, of whom 40% of these patients showed good to excellent and 20% satisfactory clinical improvement; 40% showed unsatisfactory improvement. The favourable outcome following implantation of a hydrostatic shunt thus did not correlate with decreased ventricular volume 1 year after operation, better outcomes being observed in patients with little or no alteration in ventricular size than in those with a marked decrease. Postoperative change in ventricular volume in NPH thus does not have the same significance as in patients with high-pressure hydrocephalus. (orig.)

  1. Prognostic implications of tumor volume response and COX-2 expression change during radiotherapy in cervical cancer patients

    International Nuclear Information System (INIS)

    Noh, Jae Myoung; Park, Won; Huh, Seung Jae; Cho, Eun Yoon; Choi, Yoon La; Bae, Duk Soo; Kim, Byoung Gie

    2012-01-01

    The relationship between treatment outcomes, alteration of the expression of biological markers, and tumor volume response during radiotherapy (RT) in patients with uterine cervical cancer was analyzed. Twenty patients with cervical squamous cell carcinoma received definitive RT with (n = 17) or without (n = 3) concurrent chemotherapy. Tumor volumes were measured by three serial magnetic resonance imaging scans at pre-, mid-, and post-RT. Two serial punch biopsies were performed at pre- and mid-RT, and immunohistochemical staining for cyclooxygenase (COX)-2 and epidermal growth factor receptor was performed. The median follow-up duration was 60 months. The median tumor volume response at mid-RT (V2R) was 0.396 (range, 0.136 to 0.983). At mid-RT, an interval increase in the distribution of immunoreactivity for COX-2 was observed in 8 patients, and 6 of them showed poor mid-RT tumor volume response (V2R ≥ 0.4). Four (20%) patients experienced disease progression after 10 to 12 months (median, 11 months). All 4 patients had poor mid-RT tumor volume response (p = 0.0867) and 3 of them had an interval increase in COX-2 expression. Overall survival (OS) and progression-free survival (PFS) decreased in patients with V2R ≥ 0.4 (p 0.0291 for both). An interval increase in COX-2 expression at mid-RT was also associated with a decreased survival (p = 0.1878 and 0.1845 for OS and PFS, respectively). Poor tumor volume response and an interval increase in COX-2 expression at mid-RT decreased survival outcomes in patients with uterine cervical cancer.

  2. Interfractional changes in tumour volume and position during entire radiotherapy courses for lung cancer with respiratory gating and image guidance

    DEFF Research Database (Denmark)

    Juhler-Nøttrup, Trine; Korreman, Stine Sofia; Pedersen, Anders N

    2008-01-01

    were contoured on each CT scan to evaluate the variations in volumes and position. The lung tumours and the mediastinal tumours were contoured separately. The positional variations were measured as 3D mobility vectors and correlated to matching of the scans using the two different strategies. RESULTS......-87% when matched using bony landmarks and 70-76% when matched using skin tattoos. The overlap of the mediastinal tumours were 60-65% and 41-47%, respectively. CONCLUSIONS: Despite the use of gating the tumours varied considerably, regarding both position and volume. The variations in position were...

  3. Mapping directionality specific volume changes using tensor based morphometry: an application to the study of gyrogenesis and lateralization of the human fetal brain.

    Science.gov (United States)

    Rajagopalan, Vidya; Scott, Julia; Habas, Piotr A; Kim, Kio; Rousseau, Francois; Glenn, Orit A; Barkovich, A James; Studholme, Colin

    2012-11-01

    Tensor based morphometry (TBM) is a powerful approach to analyze local structural changes in brain anatomy. However, conventional scalar TBM methods do not completely capture all direction specific volume changes required to model complex changes such as those during brain growth. In this paper, we describe novel TBM descriptors for studying direction-specific changes in a subject population which can be used in conjunction with scalar TBM to analyze local patterns in directionality of volume change during brain development. We also extend the methodology to provide a new approach to mapping directional asymmetry in deformation tensors associated with the emergence of structural asymmetry in the developing brain. We illustrate the use of these methods by studying developmental patterns in the human fetal brain, in vivo. Results show that fetal brain development exhibits a distinct spatial pattern of anisotropic growth. The most significant changes in the directionality of growth occur in the cortical plate at major sulci. Our analysis also detected directional growth asymmetry in the peri-Sylvian region and the medial frontal lobe of the fetal brain. Copyright © 2012 Elsevier Inc. All rights reserved.

  4. The effect of strain path change on subgrain volume fraction determined from in situ X-ray measurements

    DEFF Research Database (Denmark)

    Wejdemann, Christian; Poulsen, Henning Friis; Lienert, U.

    2009-01-01

    to additional 5% strain is performed in situ while mapping a selected X-ray reflection from one particular bulk grain with high angular resolution. The reciprocal space maps are analyzed with a recently developed fitting method, and a correlation is found between the evolution of the subgrain volume fraction...

  5. Nonlinear effects at volume charge polarization and calculation of the structure radiation changes in the crystals with hydrogen bonds

    International Nuclear Information System (INIS)

    Tonkonogov, M.P.; Medvedev, V.Ya.

    2003-01-01

    The formulas for volume charge distribution, complex permittivity, static dielectric constant for the crystals with hydrogen bonds are proposed. With help of the formulas the structure defect concentration, relaxation energy of relaxators were calculated for important electronic and optoelectronic materials as mica, KDP and DKDP crystals, gypsum, talk

  6. An EGS4-ready tomographic computational model of a 14-year-old female torso for calculating organ doses from CT examinations

    International Nuclear Information System (INIS)

    Caon, M.; School of Physics and Electronic Systems Engineering, University of South Australia, The Levels Campus, Mawson Lakes, South Australia, 5095; Pattison, J.

    1999-01-01

    Fifty-four consecutive CT scans have been used to construct a tomographic computational model of a 14-year-old female torso suitable for the determination of organ doses from CT. The model, known as ADELAIDE, is in the form of an input file compatible with user codes based on XYZDOS.MOR from the readily available EGS4 Monte Carlo radiation transport code. ADELAIDE's dimensions are close to the Australian averages for her age so the model is representative of a 14-year-old girl. The realistic anatomy in the model differs considerably from that in Cristy's 15-year-old mathematical computational model by having realistically shaped organs that are appropriately located within a real external contour. Average absorbed dose to organs from simulated CT examinations of the chest and abdomen have been calculated for ADELAIDE using EGS4 within a geometry specific to the General Electric Hi-Speed Advantage CT scanner and using an x-ray spectrum calculated using data from the scanner's x-ray tube. The simulations include the scanner's beam shaping filter and patient table. It is suggested that the resulting values have fewer possible sources of uncertainty than organ doses derived from dose coefficients calculated for a MIRD style model with mathematical anatomy and a spectrum that may not match that of the scanner. The organ doses were normalized using the scanner's CTDI measured free-in-air and an EGS4 simulation of the CTDI measurement. Effective dose to the torso from 26-slice chest and 24-slice abdomen examinations (at 120 kV, 200 mAs, 7 mm slices) is 4.6±0.1mSv and 4.3±0.1mSv respectively. (author)

  7. SU-F-207-03: Dosimetric Effect of the Position of Arms in Torso CT Scan with Tube Current Modulation

    International Nuclear Information System (INIS)

    Liu, H; Gao, Y; Xu, X; Zhuo, W; Wu, J

    2015-01-01

    Purpose: To evaluate the patient organ dose differences between the arms-raised and arms-lowered postures in Torso multidetector computed tomography (MDCT) scan protocols with tube current modulation (TCM). Methods: Patient CT organ doses were simulated using the Monte Carlo method with human phantoms and a validated CT scanner model. A set of adult human phantoms with arms raised and arms lowered postures were developed using advanced BREP-based mesh surface geometries. Organ doses from routine Torso scan protocols such as chest, abdomen-pelvis, and CAP scans were simulated. The organ doses differences caused by two different posutres were investigated when tube current modulation (TCM) were applied during the CT scan. Results: With TCM applied, organ doses of all the listed organs of arms-lowered posture phantom are larger than those of arms raised phantom. The dose difference for most of the organs or tissues are larger than 50%, and the skin doses difference for abdomen-pelvis scan even reaches 112.03%. This is due to the fact that the tube current for patient with arms-lowered is much higher than for the arms raised posture. Conclusion: Considering CT scan with TCM, which is commonly applied clinically, patients who could not raise their arms will receive higher radiation dose than the arms raised patient, with dose differences for some tissues such as the skin being larger than 100%. This is due to the additional tube current necessary to penetrate the arms while maintaining consistent image quality. National Nature Science Foundation of China(No.11475047)

  8. Heat transfer characteristics of UF6 in a container heated from outer surface. Pt. 1. Thermal hydraulic analysis method taking account of phase change and volume expansion

    International Nuclear Information System (INIS)

    Wataru, Masumi; Gomi, Yoshio; Yamakawa, Hidetsugu; Tsumune, Daisuke

    1995-01-01

    Natural UF6 is transported in a steel container from foreign countries to the enrichment plant in Japan. If the container meets fire accident, it is heated by fire (800degC) and rupture of the container may occur. For the safety point of view, it is necessary to know whether rupture occurs or not. Because UF6 has a radiological and chemical hazards, it is difficult to perform a demonstration test with UF6. So thermal calculation method has to be developed. The rupture is caused by UF6 gaseous pressure or volume expansion of liquid UF6. To know time history of internal pressure and temperature distribution in the container, it is important to evaluate thermal phenomena of UF6. When UF6 is heated, it changes from solid to liquid or gas at low temperature (64degC) and then its volume expands little by little. In this study, thermal calculation method has been developed taking phase change and thermal expansion of UF6 into account. In the calculation, a two-dimensional model is adopted and natural convection of liquid UF6 is analyzed. As a result of this study, numerical solutions have been obtained taking phase change and volume expansion into account. (author)

  9. Factors Affecting Volume Changes of the Somatosensory Cortex in Patients with Spinal Cord Injury: To Be Considered for Future Neuroprosthetic Design

    Directory of Open Access Journals (Sweden)

    Yvonne Höller

    2017-12-01

    Full Text Available Spinal cord injury (SCI leads to severe chronic disability, but also to secondary adaptive changes upstream to the injury in the brain which are most likely induced due to the lack of afferent information. These neuroplastic changes are a potential target for innovative therapies such as neuroprostheses, e.g., by stimulation in order to evoke sensation or in order to suppress phantom limb pain. Diverging results on gray matter atrophy have been reported in patients with SCI. Detectability of atrophy seems to depend on the selection of the regions of interest, while whole-brain approaches are not sensitive enough. In this study, we discussed previous research approaches and analyzed differential atrophic changes in incomplete SCI using manual segmentation of the somatosensory cortex. Patients with incomplete SCI (ASIA C-D, with cervical (N = 5 and thoracic (N = 6 injury were included. Time since injury was ≤12 months in 7 patients, and 144, 152, 216, and 312 months in the other patients. Age at the injury was ≤26 years in 4 patients and ≥50 years in 7 patients. A sample of 12 healthy controls was included in the study. In contrast to all previous studies that used voxel-based morphometry, we performed manual segmentation of the somatosensory cortex in the postcentral gyrus from structural magnetic resonance images and normalized the calculated volumes against the sum of volumes of an automated whole-head segmentation. Volumes were smaller in patients than in controls (p = 0.011, and as a tendency, female patients had smaller volumes than male patients (p = 0.017, uncorrected. No effects of duration (subacute vs. chronic, level of lesion (cervical vs. thoracic, region (left vs. right S1, and age at onset (≤26 vs. ≥50 years was found. Our results demonstrate volume loss of S1 in incomplete SCI and encourage further research with larger sample sizes on volumetric changes in the acute and chronic stage of SCI, in

  10. cExternal beam radiation results in minimal changes in post void residual urine volumes during the treatment of clinically localized prostate cancer

    Directory of Open Access Journals (Sweden)

    Wallner Kent E

    2009-07-01

    Full Text Available Abstract Background To evaluate the impact of external beam radiation therapy (XRT on weekly ultrasound determined post-void residual (PVR urine volumes in patients with prostate cancer. Methods 125 patients received XRT for clinically localized prostate cancer. XRT was delivered to the prostate only (n = 66 or if the risk of lymph node involvement was greater than 10% to the whole pelvis followed by a prostate boost (n = 59. All patients were irradiated in the prone position in a custom hip-fix mobilization device with an empty bladder and rectum. PVR was obtained at baseline and weekly. Multiple clinical and treatment parameters were evaluated as predictors for weekly PVR changes. Results The mean patient age was 73.9 years with a mean pre-treatment prostate volume of 53.3 cc, a mean IPSS of 11.3 and a mean baseline PVR of 57.6 cc. During treatment, PVR decreased from baseline in both cohorts with the absolute difference within the limits of accuracy of the bladder scanner. Alpha-blockers did not predict for a lower PVR during treatment. There was no significant difference in mean PVR urine volumes or differences from baseline in either the prostate only or pelvic radiation groups (p = 0.664 and p = 0.458, respectively. Patients with a larger baseline PVR (>40 cc had a greater reduction in PVR, although the greatest reduction was seen between weeks one and three. Patients with a small PVR ( Conclusion Prostate XRT results in clinically insignificant changes in weekly PVR volumes, suggesting that radiation induced bladder irritation does not substantially influence bladder residual urine volumes.

  11. Tree water storage and its diurnal dynamics related to sap flow and changes in stem volume in old-growth Douglas-fir trees.

    Science.gov (United States)

    Cermák, Jan; Kucera, Jiri; Bauerle, William L; Phillips, Nathan; Hinckley, Thomas M

    2007-02-01

    Diurnal and seasonal tree water storage was studied in three large Douglas-fir (Pseudotsuga menziesii [Mirb.] Franco) trees at the Wind River Canopy Crane Research site. Changes in water storage were based on measurements of sap flow and changes in stem volume and tissue water content at different heights in the stem and branches. We measured sap flow by two variants of the heat balance method (with internal heating in stems and external heating in branches), stem volume with electronic dendrometers, and tissue water content gravimetrically. Water storage was calculated from the differences in diurnal courses of sap flow at different heights and their integration. Old-growth Douglas-fir trees contained large amounts of free water: stem sapwood was the most important storage site, followed by stem phloem, branch sapwood, branch phloem and needles. There were significant time shifts (minutes to hours) between sap flow measured at different positions within the transport system (i.e., stem base to shoot tip), suggesting a highly elastic transport system. On selected fine days between late July and early October, when daily transpiration ranged from 150 to 300 liters, the quantity of stored water used daily ranged from 25 to 55 liters, i.e., about 20% of daily total sap flow. The greatest amount of this stored water came from the lower stem; however, proportionally more water was removed from the upper parts of the tree relative to their water storage capacity. In addition to lags in sap flow from one point in the hydrolic pathway to another, the withdrawal and replacement of stored water was reflected in changes in stem volume. When point-to-point lags in sap flow (minutes to hours near the top and stem base, respectively) were considered, there was a strong linear relationship between stem volume changes and transpiration. Volume changes of the whole tree were small (equivalent to 14% of the total daily use of stored water) indicating that most stored water came from

  12. Mild hypothermia attenuates changes in respiratory system mechanics and modifies cytokine concentration in bronchoalveolar lavage fluid during low lung volume ventilation.

    Science.gov (United States)

    Dostál, P; Senkeřík, M; Pařízková, R; Bareš, D; Zivný, P; Zivná, H; Cerný, V

    2010-01-01

    Hypothermia was shown to attenuate ventilator-induced lung injury due to large tidal volumes. It is unclear if the protective effect of hypothermia is maintained under less injurious mechanical ventilation in animals without previous lung injury. Tracheostomized rats were randomly allocated to non-ventilated group (group C) or ventilated groups of normothermia (group N) and mild hypothermia (group H). After two hours of mechanical ventilation with inspiratory fraction of oxygen 1.0, respiratory rate 60 min(-1), tidal volume 10 ml x kg(-1), positive end-expiratory pressure (PEEP) 2 cm H2O or immediately after tracheostomy in non-ventilated animals inspiratory pressures were recorded, rats were sacrificed, pressure-volume (PV) curve of respiratory system constructed, bronchoalveolar lavage (BAL) fluid and aortic blood samples obtained. Group N animals exhibited a higher rise in peak inspiratory pressures in comparison to group H animals. Shift of the PV curve to right, higher total protein and interleukin-6 levels in BAL fluid were observed in normothermia animals in comparison with hypothermia animals and non-ventilated controls. Tumor necrosis factor-alpha was lower in the hypothermia group in comparison with normothermia and non-ventilated groups. Mild hypothermia attenuated changes in respiratory system mechanics and modified cytokine concentration in bronchoalveolar lavage fluid during low lung volume ventilation in animals without previous lung injury.

  13. Direct linear measurement of root dentin thickness and dentin volume changes with post space preparation: A cone-beam computed tomography study

    Directory of Open Access Journals (Sweden)

    Shoeb Yakub Shaikh

    2018-01-01

    Full Text Available Aim: The purpose of the present study was direct linear measurement of dentin thickness and dentin volume changes for post space preparation with cone-beam computed tomography (CBCT. Materials and Methods: Ten maxillary central incisors were scanned, before and after root canal and post space preparation, with Orthophos XG three-dimensional hybrid unit. Thirteen axial section scans of each tooth from orifice to apex and dentin thickness for buccal, lingual, mesial, and distal were measured using proprietary measuring tool and thereafter subjected to statistical analysis. Furthermore, dentin volume was evaluated using ITK-SNAP software. Results: There was statistically significant difference between the dentin thickness in pre- and postinstrumentation (paired t-test and also between different groups (one-way ANOVA. In the shortest post length of 4.5mm the post space preparation resulted in 2.17% loss of hard tissue volume, where as 11mm longest post length post space preparation resulted in >40% loss of hard tissue volume. Conclusion: CBCT axial section scan for direct measurements of root dentin thickness can be guideline before and after post space preparation for selection of drill length and diameter.

  14. 40Ar/39Ar geochronology and volume estimates of the Tasmantid Seamounts: Support for a change in the motion of the Australian plate

    Science.gov (United States)

    Crossingham, Tracey J.; Vasconcelos, Paulo M.; Cunningham, Toby; Knesel, Kurt M.

    2017-09-01

    New volume estimates and 40Ar/39Ar ages for the Tasmantid Seamounts are reported to investigate the origin of volcanism and potential links between volcanism and changes in the speed and direction of migration of the Australian plate during the Cenozoic. The results show that the average extrusive volume of individual volcanoes along the seamount chain is 2587 ± 3078 km3 (1 s), and that volumes generally increase towards the south. An exception, the Britannia Guyot, located in the middle of the seamount chain, is the most voluminous (11,374 km3). Nineteen new 40Ar/39Ar ages, from Wreck to Gascoyne, show that the emplacement of the Tasmantid Seamounts occurred between 33.2 ± 1.5 and 6.5 ± 0.6 Ma. A single linear regression applied to the age versus latitude data, assuming volcanism to be caused by plate migration over a stationary hotspot, reveals a plate migration rate of 62 ± 2 kmMa- 1 (R2 = 0.97; n = 27) between 33 and 6 Ma. However, the bend in the seamount track, corresponding with the period of largest eruptive volumes, suggests three distinct segments in the Tasmantid age versus latitude data. The northern segment is consistent with a plate migration rate of 75 ± 10 kmMa- 1 (R2 = 0.88; n = 10) and the southern segment reveals a plate migration rate of 64 ± 4 kmMa- 1 (R2 = 0.94; n = 17). The period between these two segments, from 25 to 19 Ma, overlaps with the period of slow migration and change in the direction of the Australian plate derived from the age versus latitude distribution of continental central volcanoes. The new Tasmantid Seamount results support the interpretation that there were changes in the velocity and direction to Australia's northward trajectory, possibly resulting from a series of collisional events.

  15. Three Decades of Volume Change of a Small Greenlandic Glacier Using Ground Penetrating Radar, Structure from Motion, and Aerial Photogrammetry

    DEFF Research Database (Denmark)

    Marcer, M.; Stentoft, Peter Alexander; Bjerre, Elisa

    2017-01-01

    Glaciers in the Arctic are losing mass at an increasing rate. Here we use surface topography derived from Structure from Motion (SfM) and ice volume from ground penetrating radar (GPR) to describe the 2014 state of Aqqutikitsoq glacier (2.85 km) on Greenland's west coast. A photogrammetrically...... derived 1985 digital elevation model (DEM) was subtracted from a 2014 DEM obtained using land-based SfM to calculate geodetic glacier mass balance. Furthermore, a detailed 2014 ground penetrating radar survey was performed to assess ice volume. From 1985 to 2014, the glacier has lost 49.8 ± 9.4 10 m...... aerial photography. To address this issue, surface elevation in low contrast areas was measured manually at point locations and interpolated using a universal kriging approach. We conclude that ground-based SfM is well suited to establish high-quality DEMs of smaller glaciers. Provided favorable...

  16. Changes in the volume, power and nutritional quality of foods marketed to children on television in Canada.

    Science.gov (United States)

    Potvin Kent, Monique; Martin, Cherie L; Kent, Emily A

    2014-09-01

    To evaluate the self-regulatory Children's Food and Beverage Advertising Initiative pre- and post-implementation in terms of volume of marketing, marketing techniques, and nutritional quality of foods marketed to children on television. Data for 11 food categories for May 2006 and 2011 were purchased from Nielsen Media Research for two children's specialty channels in Toronto. A content analysis of food advertisements examining the volume and marketing techniques was undertaken. Nutritional information on each advertisement was collected and comparisons were made between 2006 and 2011. The volume of ads aired by Canadian Children's Food and Beverage Advertising Initiative (CAI) companies on children's specialty channels decreased by 24% between 2006 and 2011; however, children and teens were targeted significantly more, and spokes-characters and licensed characters were used more frequently in 2011 compared to 2006. The overall nutritional quality of CAI advertisements remains unchanged between 2006 and 2011. There are clear weaknesses in the self-regulatory system in Canada. Food advertising needs to be regulated to protect the health of Canadian children. © 2014 The Authors Obesity published by Wiley Periodicals, Inc. on behalf of The Obesity Society (TOS).

  17. Changes in the volume, power and nutritional quality of foods marketed to children on television in Canada

    Science.gov (United States)

    Potvin Kent, Monique; Martin, Cherie L; Kent, Emily A

    2014-01-01

    Objective To evaluate the self-regulatory Children's Food and Beverage Advertising Initiative pre- and post-implementation in terms of volume of marketing, marketing techniques, and nutritional quality of foods marketed to children on television. Methods Data for 11 food categories for May 2006 and 2011 were purchased from Nielsen Media Research for two children's specialty channels in Toronto. A content analysis of food advertisements examining the volume and marketing techniques was undertaken. Nutritional information on each advertisement was collected and comparisons were made between 2006 and 2011. Results The volume of ads aired by Canadian Children's Food and Beverage Advertising Initiative (CAI) companies on children's specialty channels decreased by 24% between 2006 and 2011; however, children and teens were targeted significantly more, and spokes-characters and licensed characters were used more frequently in 2011 compared to 2006. The overall nutritional quality of CAI advertisements remains unchanged between 2006 and 2011. Conclusion There are clear weaknesses in the self-regulatory system in Canada. Food advertising needs to be regulated to protect the health of Canadian children. PMID:24975614

  18. Three Decades of Volume Change of a Small Greenlandic Glacier Using Ground Penetrating Radar, Structure from Motion, and Aerial Photogrammetry

    DEFF Research Database (Denmark)

    Marcer, M.; Stentoft, Peter Alexander; Bjerre, Elisa

    2017-01-01

    of ice, corresponding to roughly a quarter of its 1985 volume (148.6 ± 47.6 10 m) and a thinning rate of 0.60 ± 0.11 m a. The computations are challenged by a relatively large fraction of the 1985 DEM (∼50% of the glacier surface) being deemed unreliable owing to low contrast (snow cover) in the 1985......Glaciers in the Arctic are losing mass at an increasing rate. Here we use surface topography derived from Structure from Motion (SfM) and ice volume from ground penetrating radar (GPR) to describe the 2014 state of Aqqutikitsoq glacier (2.85 km) on Greenland's west coast. A photogrammetrically...... derived 1985 digital elevation model (DEM) was subtracted from a 2014 DEM obtained using land-based SfM to calculate geodetic glacier mass balance. Furthermore, a detailed 2014 ground penetrating radar survey was performed to assess ice volume. From 1985 to 2014, the glacier has lost 49.8 ± 9.4 10 m...

  19. Labyrinth and cerebral-spinal fluid pressure changes in guinea pigs and monkeys during simulated zero G

    Science.gov (United States)

    Parker, D. E.

    1977-01-01

    This study was undertaken to explore the hypothesis that shifts of body fluids from the legs and torso toward the head contribute to the motion sickness experienced by astronauts and cosmonauts. The shifts in body fluids observed during zero-G exposure were simulated by elevating guinea pigs' and monkeys' torsos and hindquarters. Cerebral-spinal fluid pressure was recorded from a transducer located in a brain ventricle; labyrinth fluid pressure was recorded from a pipette cemented in a hole in a semicircular canal. An anticipated divergence in cerebral-spinal fluid pressure and labyrinth fluid pressure during torso elevation was not observed. The results of this study do not support a fluid shift mechanism of zero-G-induced motion sickness. However, a more complete test of the fluid shift mechanism would be obtained if endolymph and perilymph pressure changes were determined separately; we have been unable to perform this test to date.

  20. TU-G-BRA-05: Predicting Volume Change of the Tumor and Critical Structures Throughout Radiation Therapy by CT-CBCT Registration with Local Intensity Correction

    Energy Technology Data Exchange (ETDEWEB)

    Park, S; Robinson, A; Kiess, A; Quon, H; Wong, J; Lee, J [Johns Hopkins University, Baltimore, MD (United States); Plishker, W [IGI Technologies Inc., College Park, MD (United States); Shekhar, R [IGI Technologies Inc., College Park, MD (United States); Children’s National Medical Center, Washington, D.C. (United States)

    2015-06-15

    Purpose: The purpose of this study is to develop an accurate and effective technique to predict and monitor volume changes of the tumor and organs at risk (OARs) from daily cone-beam CTs (CBCTs). Methods: While CBCT is typically used to minimize the patient setup error, its poor image quality impedes accurate monitoring of daily anatomical changes in radiotherapy. Reconstruction artifacts in CBCT often cause undesirable errors in registration-based contour propagation from the planning CT, a conventional way to estimate anatomical changes. To improve the registration and segmentation accuracy, we developed a new deformable image registration (DIR) that iteratively corrects CBCT intensities using slice-based histogram matching during the registration process. Three popular DIR algorithms (hierarchical B-spline, demons, optical flow) augmented by the intensity correction were implemented on a graphics processing unit for efficient computation, and their performances were evaluated on six head and neck (HN) cancer cases. Four trained scientists manually contoured nodal gross tumor volume (GTV) on the planning CT and every other fraction CBCTs for each case, to which the propagated GTV contours by DIR were compared. The performance was also compared with commercial software, VelocityAI (Varian Medical Systems Inc.). Results: Manual contouring showed significant variations, [-76, +141]% from the mean of all four sets of contours. The volume differences (mean±std in cc) between the average manual segmentation and four automatic segmentations are 3.70±2.30(B-spline), 1.25±1.78(demons), 0.93±1.14(optical flow), and 4.39±3.86 (VelocityAI). In comparison to the average volume of the manual segmentations, the proposed approach significantly reduced the estimation error by 9%(B-spline), 38%(demons), and 51%(optical flow) over the conventional mutual information based method (VelocityAI). Conclusion: The proposed CT-CBCT registration with local CBCT intensity correction

  1. Changes in Tear Volume after 3% Diquafosol Treatment in Patients with Dry Eye Syndrome: An Anterior Segment Spectral-domain Optical Coherence Tomography Study.

    Science.gov (United States)

    Lee, Kwan Bok; Koh, Kyung Min; Kwon, Young A; Song, Sang Wroul; Kim, Byoung Yeop; Chung, Jae Lim

    2017-08-01

    To evaluate changes in the tear meniscus area and tear meniscus height over time in patients with dry eye syndrome, using anterior segment spectral-domain optical coherence tomography after the instillation of 3% diquafosol ophthalmic solution. Sixty eyes from 30 patients with mild to moderate dry eye syndrome were included. Tear meniscus images acquired by anterior segment spectral-domain optical coherence tomography were analyzed using National Institutes of Health's image-analysis software (ImageJ 1.44p). Tear meniscus area and tear meniscus height were measured at baseline, 5 minutes, 10 minutes, and 30 minutes after instillation of a drop of diquafosol in one eye and normal saline in the other eye. Changes in ocular surface disease index score, tear film break-up time, corneal staining score by Oxford schema, and meibomian expressibility were also evaluated at baseline, and after 1 week and 1 month of a diquafosol daily regimen. Sixty eyes from 30 subjects (mean age, 29.3 years; 8 men and 22 women) were included. In eyes receiving diquafosol, tear volume was increased at 5 and 10 minutes compared with baseline. It was also higher than saline instilled eyes at 5, 10, and 30 minutes. Changes in tear volume with respect to baseline were not statistically different after the use of diquafosol for 1 month. Ocular surface disease index score, tear film break-up time, and Oxford cornea stain score were significantly improved after 1 week and 1 month of daily diquafosol instillation, but meibomian expressibility did not change. Topical diquafosol ophthalmic solution effectively increased tear volume for up to 30 minutes, compared to normal saline in patients with dry eye syndrome. © 2017 The Korean Ophthalmological Society

  2. Changes in Hippocampal Volume are Correlated with Cell Loss but Not with Seizure Frequency in Two Chronic Models of Temporal Lobe Epilepsy

    Science.gov (United States)

    Polli, Roberson S.; Malheiros, Jackeline M.; dos Santos, Renan; Hamani, Clement; Longo, Beatriz M.; Tannús, Alberto; Mello, Luiz E.; Covolan, Luciene

    2014-01-01

    Kainic acid (KA) or pilocarpine (PILO) have been used in rats to model human temporal lobe epilepsy (TLE) but the distribution and severity of structural lesions between these two models may differ. Magnetic resonance imaging (MRI) studies have used quantitative measurements of hippocampal T2 (T2HP) relaxation time and volume, but simultaneous comparative results have not been reported yet. The aim of this study was to compare the MRI T2HP and volume with histological data and frequency of seizures in both models. KA- and PILO-treated rats were imaged with a 2 T MRI scanner. T2HP and volume values were correlated with the number of cells, mossy fiber sprouting, and spontaneous recurrent seizures (SRS) frequency over the 9 months following status epilepticus (SE). Compared to controls, KA-treated rats had unaltered T2HP, pronounced reduction in hippocampal volume and concomitant cell reduction in granule cell layer, CA1 and CA3 at 3 months post SE. In contrast, hippocampal volume was unchanged in PILO-treated animals despite detectable increased T2HP and cell loss in granule cell layer, CA1 and CA3. In the following 6 months, MRI hippocampal volume remained stable with increase of T2HP signal in the KA-treated group. The number of CA1 and CA3 cells was smaller than age-matched CTL group. In contrast, PILO group had MRI volumetric reduction accompanied by reduction in the number of CA1 and CA3 cells. In this group, T2HP signal was unaltered at 6 or 9 months after status. Reductions in the number of cells were not progressive in both models. Notably, the SRS frequency was higher in PILO than in the KA model. The volumetry data correlated well with tissue damage in the epileptic brain, suggesting that MRI may be useful for tracking longitudinal hippocampal changes, allowing the assessment of individual variability and disease progression. Our results indicate that the temporal changes in hippocampal morphology are distinct for both models of TLE and that

  3. WE-G-BRD-07: Investigation of Distal Lung Atelectasis Following Stereotactic Body Radiation Therapy Using Regional Lung Volume Changes Between Pre- and Post- Treatment CT Scans

    Energy Technology Data Exchange (ETDEWEB)

    Diot, Q; Kavanagh, B; Miften, M [University of Colorado School of Medicine, Aurora, CO (United States)

    2014-06-15

    Purpose: To propose a quantitative method using lung deformations to differentiate between radiation-induced fibrosis and potential airway stenosis with distal atelectasis in patients treated with stereotactic body radiation therapy (SBRT) for lung tumors. Methods: Twenty-four lung patients with large radiation-induced density increases outside the high dose region had their pre- and post-treatment CT scans manually registered. They received SBRT treatments at our institution between 2002 and 2009 in 3 or 5 fractions, to a median total dose of 54Gy (range, 30–60). At least 50 anatomical landmarks inside the lung (airway branches) were paired for the pre- and post-treatment scans to guide the deformable registration of the lung structure, which was then interpolated to the whole lung using splines. Local volume changes between the planning and follow-up scans were calculated using the deformation field Jacobian. Hyperdense regions were classified as atelectatic or fibrotic based on correlations between regional density increases and significant volume contractions compared to the surrounding tissues. Results: Out of 24 patients, only 7 demonstrated a volume contraction that was at least one σ larger than the remaining lung average. Because they did not receive high doses, these shrunk hyperdense regions were likely showing distal atelectasis resulting from radiation-induced airway stenosis rather than conventional fibrosis. On average, the hyperdense regions extended 9.2 cm farther than the GTV contours but not significantly more than 8.6 cm for the other patients (p>0.05), indicating that a large offset between the radiation and hyperdense region centers is not a good surrogate for atelectasis. Conclusion: A method based on the relative comparison of volume changes between different dates was developed to identify potential lung regions experiencing distal atelectasis. Such a tool is essential to study which lung structures need to be avoided to prevent

  4. Reanalysis of multi-temporal aerial images of Storglaciären, Sweden (1959–99 – Part 1: Determination of length, area, and volume changes

    Directory of Open Access Journals (Sweden)

    W. Haeberli

    2010-09-01

    Full Text Available Storglaciären, located in the Kebnekaise massif in northern Sweden, has a long history of glaciological research. Early photo documentations date back to the late 19th century. Measurements of front position variations and distributed mass balance have been carried out since 1910 and 1945/46, respectively. In addition to these in-situ measurements, aerial photographs have been taken at decadal intervals since the beginning of the mass balance monitoring program and were used to produce topographic glacier maps. Inaccuracies in the maps were a challenge to early attempts to derive glacier volume changes and resulted in major differences when compared to the direct glaciological mass balances. In this study, we reanalyzed dia-positives of the original aerial photographs of 1959, -69, -80, -90 and -99 based on consistent photogrammetric processing. From the resulting digital elevation models and orthophotos, changes in length, area, and volume of Storglaciären were computed between the survey years, including an assessment of related errors. Between 1959 and 1999, Storglaciären lost an ice volume of 19×106 m3, which corresponds to a cumulative ice thickness loss of 5.69 m and a mean annual loss of 0.14 m. This ice loss resulted largely from a strong volume loss during the period 1959–80 and was partly compensated during the period 1980–99. As a consequence, the glacier shows a strong retreat in the 1960s, a slowing in the 1970s, and pseudo-stationary conditions in the 1980s and 1990s.

  5. Implications for dosimetric changes when introducing MR-guided brachytherapy for small volume cervix cancer: a comparison of CT and MR-based treatments in a single centre

    International Nuclear Information System (INIS)

    Dempsey, Claire; Govindarajulu, Geetha; Sridharan, Swetha; Capp, Anne; O'Brien, Peter

    2014-01-01

    To evaluate cervix brachytherapy dosimetry with the introduction of magnetic resonance (MR) based treatment planning and volumetric prescriptions and propose a method for plan evaluation in the transition period. The treatment records of 69 patients were reviewed retrospectively. Forty one patients were treated using computed tomography (CT)-based, Point A-based prescriptions and 28 patients were treated using magnetic resonance (MR)-based, volumetric prescriptions. Plans were assessed for dose to Point A and organs at risk (OAR) with additional high-risk clinical target volume (HR-CTV) dose assessment for MR-based brachytherapy plans. ICRU-38 point doses and GEC-ESTRO recommended volumetric doses (D2 cc for OAR and D 100 , D 98 and D 90 for HR-CTV) were also considered. For patients with small HR-CTV sizes, introduction of MR-based volumetric brachytherapy produced a change in dose delivered to Point A and OAR. Point A doses fell by 4.8 Gy (p = 0.0002) and ICRU and D 2cc doses for OAR also reduced (p < 0.01). Mean Point A doses for MR-based brachytherapy treatment plans were closer to those of HR-CTV D 100 for volumes less than 20 cm 3 and HR-CTV D 98 for volumes between 20 and 35 cm 3 , with a significant difference (p < 0.0001) between Point A and HR-CTV D 90 doses in these ranges. In order to maintain brachytherapy dose consistency across varying HR-CTV sizes there must be a relationship between the volume of the HR-CTV and the prescription dose. Rather than adopting a ‘one size fits all’ approach during the transition to volume-based prescriptions, this audit has shown that separating prescription volumes into HR-CTV size categories of less than 20 cm 3 , between 20 and 35 cm 3 , and more than 35 cm 3 the HR-CTV can provide dose uniformity across all volumes and can be directly linked to traditional Point A prescriptions.

  6. Wilderness science in a time of change conference-Volume 1: Changing perspectives and future directions; 1999 May 23-27; Missoula, MT

    Science.gov (United States)

    David N. Cole; Stephen F. McCool; Wayne A. Freimund; Jennifer O' Loughlin

    2000-01-01

    Ten papers presented as plenary talks at the conference, "Wilderness Science in a Time of Change," are included. Topics include: the influence of global change on wilderness and its management; contemporary criticisms and celebrations of the wilderness idea; the capacity of science to meet the challenges and opportunities wilderness presents; wilderness in...

  7. Dynamic changes in water ADC, energy metabolism, extracellular space volume and tortuosity in neonatal rat brain during irreversible ischemia

    NARCIS (Netherlands)

    Toorn, van der A.; Syková, E.; Dijkhuizen, R.M.; Voríšek, I.; Vargová, L.; Skobisová, E.; Lookeren Campagne, van M.; Reese, T.; Nicolaij, K.

    1996-01-01

    To obtain a better understanding of the mechanisms underlying early changes in the brain water apparent diffusion coefficient (ADC) observed in cerebral ischemia, dynamic changes in the ADC of water and in the energy status were measured at postnatal day 8 or 9 in neonatal rat brains after cardiac

  8. Predictive and prognostic value of tumor volume and its changes during radical radiotherapy of stage III non-small cell lung cancer. A systematic review

    International Nuclear Information System (INIS)

    Kaesmann, Lukas; Niyazi, Maximilian; Fleischmann, Daniel; Blanck, Oliver; Baumann, Rene; Baues, Christian; Klook, Lisa; Rosenbrock, Johannes; Trommer-Nestler, Maike; Dobiasch, Sophie; Eze, Chukwuka; Gauer, Tobias; Goy, Yvonne; Giordano, Frank A.; Sautter, Lisa; Hausmann, Jan; Henkenberens, Christoph; Kaul, David; Thieme, Alexander H.; Krug, David; Schmitt, Daniela; Maeurer, Matthias; Panje, Cedric M.; Suess, Christoph; Ziegler, Sonia; Ebert, Nadja; Medenwald, Daniel; Ostheimer, Christian

    2018-01-01

    Lung cancer remains the leading cause of cancer-related mortality worldwide. Stage III non-small cell lung cancer (NSCLC) includes heterogeneous presentation of the disease including lymph node involvement and large tumour volumes with infiltration of the mediastinum, heart or spine. In the treatment of stage III NSCLC an interdisciplinary approach including radiotherapy is considered standard of care with acceptable toxicity and improved clinical outcome concerning local control. Furthermore, gross tumour volume (GTV) changes during definitive radiotherapy would allow for adaptive replanning which offers normal tissue sparing and dose escalation. A literature review was conducted to describe the predictive value of GTV changes during definitive radiotherapy especially focussing on overall survival. The literature search was conducted in a two-step review process using PubMed registered /Medline registered with the key words ''stage III non-small cell lung cancer'' and ''radiotherapy'' and ''tumour volume'' and ''prognostic factors''. After final consideration 17, 14 and 9 studies with a total of 2516, 784 and 639 patients on predictive impact of GTV, GTV changes and its impact on overall survival, respectively, for definitive radiotherapy for stage III NSCLC were included in this review. Initial GTV is an important prognostic factor for overall survival in several studies, but the time of evaluation and the value of histology need to be further investigated. GTV changes during RT differ widely, optimal timing for re-evaluation of GTV and their predictive value for prognosis needs to be clarified. The prognostic value of GTV changes is unclear due to varying study qualities, re-evaluation time and conflicting results. The main findings were that the clinical impact of GTV changes during definitive radiotherapy is still unclear due to heterogeneous study designs with varying quality

  9. Maternal nutritional status in early pregnancy is associated with body water and plasma volume changes in a pregnancy cohort in rural Bangladesh.

    Science.gov (United States)

    Gernand, Alison D; Christian, Parul; Schulze, Kerry J; Shaikh, Saijuddin; Labrique, Alain B; Shamim, Abu Ahmed; West, Keith P

    2012-06-01

    Plasma volume expansion has been associated with fetal growth. Our objective was to examine the associations between maternal nutritional status in early pregnancy and extracellular water (ECW), total body water (TBW), and percentage plasma volume change across pregnancy. In a subsample of 377 pregnant women participating in a cluster-randomized trial of micronutrient supplementation, hemoglobin, hematocrit, and multi-frequency bioelectrical impedance were measured at ~10, 20, and 32 wk of gestation. In early pregnancy, women were short (mean ± SD, 148.9 ± 5.3 cm) and thin (19.5 ± 2.5 kg/m(2)). In mixed-effects multiple regression models, a 1-unit higher BMI at ~10 wk was associated with higher ECW and TBW (0.27 and 0.66 kg per kg/m(2), respectively; P pregnancy BMI was negatively associated with gains in ECW and TBW (-0.06 and -0.14 kg per kg/m(2), respectively; P pregnancy have lower ECW and TBW in early, mid, and late pregnancy and lower late pregnancy plasma volume expansion, potentially increasing risk of fetal growth restriction.

  10. Atlas based brain volumetry: How to distinguish regional volume changes due to biological or physiological effects from inherent noise of the methodology.

    Science.gov (United States)

    Opfer, Roland; Suppa, Per; Kepp, Timo; Spies, Lothar; Schippling, Sven; Huppertz, Hans-Jürgen

    2016-05-01

    Fully-automated regional brain volumetry based on structural magnetic resonance imaging (MRI) plays an important role in quantitative neuroimaging. In clinical trials as well as in clinical routine multiple MRIs of individual patients at different time points need to be assessed longitudinally. Measures of inter- and intrascanner variability are crucial to understand the intrinsic variability of the method and to distinguish volume changes due to biological or physiological effects from inherent noise of the methodology. To measure regional brain volumes an atlas based volumetry (ABV) approach was deployed using a highly elastic registration framework and an anatomical atlas in a well-defined template space. We assessed inter- and intrascanner variability of the method in 51 cognitively normal subjects and 27 Alzheimer dementia (AD) patients from the Alzheimer's Disease Neuroimaging Initiative by studying volumetric results of repeated scans for 17 compartments and brain regions. Median percentage volume differences of scan-rescans from the same scanner ranged from 0.24% (whole brain parenchyma in healthy subjects) to 1.73% (occipital lobe white matter in AD), with generally higher differences in AD patients as compared to normal subjects (e.g., 1.01% vs. 0.78% for the hippocampus). Minimum percentage volume differences detectable with an error probability of 5% were in the one-digit percentage range for almost all structures investigated, with most of them being below 5%. Intrascanner variability was independent of magnetic field strength. The median interscanner variability was up to ten times higher than the intrascanner variability. Copyright © 2016 Elsevier Inc. All rights reserved.

  11. Interfractional changes in tumour volume and position during entire radiotherapy courses for lung cancer with respiratory gating and image guidance

    Energy Technology Data Exchange (ETDEWEB)

    Juhler-Noettrup, Trine; Korreman, Stine S.; Pedersen, Anders N.; Persson, Gitte F.; Aarup, Lasse R.; Nystroem, Haakan; Olsen, Mikael; Tarnavski, Nikolai; Specht, Lena (Dept. of Radiation Oncology, The Finsen Centre, Copenhagen (Denmark))

    2008-08-15

    Introduction. With the purpose of implementing gated radiotherapy for lung cancer patients, this study investigated the interfraction variations in tumour size and internal displacement over entire treatment courses. To explore the potential of image guided radiotherapy (IGRT) the variations were measured using a set-up strategy based on imaging of bony landmarks and compared to a strategy using in room lasers, skin tattoos and cupper landmarks. Materials and methods. During their six week treatment course of 60Gy in 2Gy fractions, ten patients underwent 3 respiratory gated CT scans. The tumours were contoured on each CT scan to evaluate the variations in volumes and position. The lung tumours and the mediastinal tumours were contoured separately. The positional variations were measured as 3D mobility vectors and correlated to matching of the scans using the two different strategies. Results. The tumour size was significantly reduced from the first to the last CT scan. For the lung tumours the reduction was 19%, p=0.03, and for the mediastinal tumours the reduction was 34%, p=0.0007. The mean 3D mobility vector and the SD for the lung tumours was 0.51cm (+-0.21) for matching using bony landmarks and 0.85cm (+-0.54) for matching using skin tattoos. For the mediastinal tumours the corresponding vectors and SD's were 0.55cm (+-0.19) and 0.72cm (+-0.43). The differences between the vectors were significant for the lung tumours p=0.004. The interfractional overlap of lung tumours was 80-87% when matched using bony landmarks and 70-76% when matched using skin tattoos. The overlap of the mediastinal tumours were 60-65% and 41-47%, respectively. Conclusions. Despite the use of gating the tumours varied considerably, regarding both position and volume. The variations in position were dependent on the set-up strategy. Set-up using IGRT was superior to set-up using skin tattoos.

  12. Interfractional changes in tumour volume and position during entire radiotherapy courses for lung cancer with respiratory gating and image guidance

    International Nuclear Information System (INIS)

    Juhler-Noettrup, Trine; Korreman, Stine S.; Pedersen, Anders N.; Persson, Gi tte F.; Aarup, Lasse R.; Nystroem, Haakan; Olsen, Mikael; Tarnavski, Nikolai; Sp echt, Lena

    2008-01-01

    Introduction. With the purpose of implementing gated radiotherapy for lung cancer patients, this study investigated the interfraction variations in tumour size and internal displacement over entire treatment courses. To explore the potential of image guided radiotherapy (IGRT) the variations were measured using a set-up strategy based on imaging of bony landmarks and compared to a strategy using in room lasers, skin tattoos and cupper landmarks. Materials and methods. During their six week treatment course of 60Gy in 2Gy fractions, ten patients underwent 3 respiratory gated CT scans. The tumours were contoured on each CT scan to evaluate the variations in volumes and position. The lung tumours and the mediastinal tumours were contoured separately. The positional variations were measured as 3D mobility vectors and correlated to matching of the scans using the two different strategies. Results. The tumour size was significantly reduced from the first to the last CT scan. For the lung tumours the reduction was 19%, p=0.03, and for the mediastinal tumours the reduction was 34%, p=0.0007. The mean 3D mobility vector and the SD for the lung tumours was 0.51cm (±0.21) for matching using bony landmarks and 0.85cm (±0.54) for matching using skin tattoos. For the mediastinal tumours the corresponding vectors and SD's were 0.55cm (±0.19) and 0.72cm (±0.43). The differences between the vectors were significant for the lung tumours p=0.004. The interfractional overlap of lung tumours was 80-87% when matched using bony landmarks and 70-76% when matched using skin tattoos. The overlap of the mediastinal tumours were 60-65% and 41-47%, respectively. Conclusions. Despite the use of gating the tumours varied considerably, regarding both position and volume. The variations in position were dependent on the set-up strategy. Set-up using IGRT was superior to set-up using skin tattoos

  13. The KCNQ5 potassium channel from mouse: a broadly expressed M-current like potassium channel modulated by zinc, pH, and volume changes

    DEFF Research Database (Denmark)

    Jensen, Henrik Sindal; Callø, Kirstine; Jespersen, Thomas

    2005-01-01

    H-dependent potentiation by Zn2+ (EC50 = 21.8 microM at pH 7.4), inhibition by acidification (IC50 = 0.75 microM; pKa = 6.1), and regulation by small changes in cell volume. Furthermore, the channels are activated by the anti-convulsant drug retigabine (EC50 = 2.0 microM) and inhibited by the M-current blockers...... and hippocampus. This study shows that murine KCNQ5 channels, in addition to sharing biophysical and pharmacological characteristics with the human ortholog, are tightly regulated by physiological stimuli such as changes in extracellular Zn2+, pH, and tonicity, thus adding to the complex regulation...

  14. Parallel Changes in Intracellular Water Volume and pH Induced by NH3/NH4+ Exposure in Single Neuroblastoma Cells

    Directory of Open Access Journals (Sweden)

    Víctor M. Blanco

    2013-12-01

    Full Text Available Background: Increased blood levels of ammonia (NH3 and ammonium (NH4+, i.e. hyperammonemia, leads to cellular brain edema in humans with acute liver failure. The pathophysiology of this edema is poorly understood. This is partly due to incomplete understanding of the osmotic effects of the pair NH3/NH4+ at the cellular and molecular levels. Cell exposure to solutions containing NH3/NH4+ elicits changes in intracellular pH (pHi, which can in turn affect cell water volume (CWV by activating transport mechanisms that produce net gain or loss of solutes and water. The occurrence of CWV changes caused by NH3/NH4+ has long been suspected, but the mechanisms, magnitude and kinetics of these changes remain unknown. Methods: Using fluorescence imaging microscopy we measured, in real time, parallel changes in pHi and CWV caused by brief exposure to NH3/NH4+ of single cells (N1E-115 neuroblastoma or NG-108 neuroblastoma X glioma loaded with the fluorescent indicator BCECF. Changes in CWV were measured by exciting BCECF at its intracellular isosbestic wavelength (∼438 nm, and pHi was measured ratiometrically. Results: Brief exposure to isosmotic solutions (i.e. having the same osmolality as that of control solutions containing NH4Cl (0.5- 30 mM resulted in a rapid, dose-dependent swelling, followed by isosmotic regulatory volume decrease (iRVD. NH4Cl solutions in which either extracellular [NH3] or [NH4+] was kept constant while the other was changed by varying the pH of the solution, demonstrated that [NH3]o rather than [NH4+]o is the main determinant of the NH4Cl-induced swelling. The iRVD response was sensitive to the anion channel blocker NPPB, and partly dependent on external Ca2+. Upon removal of NH4Cl, cells shrank and displayed isosmotic regulatory volume increase (iRVI. Regulatory volume responses could not be activated by comparable CWV changes produced by anisosmotic solutions, suggesting that membrane stretch or contraction by themselves are

  15. Noninvasive, low-noise, fast imaging of blood volume and deoxygenation changes in muscles using light-emitting diode continuous-wave imager

    Science.gov (United States)

    Lin, Yuanqing; Lech, Gwen; Nioka, Shoko; Intes, Xavier; Chance, Britton

    2002-08-01

    This article focuses on optimizing the signal to noise ratio (SNR) of a three-wavelength light-emitting diode (LED) near-infrared continuous-wave (cw) imager and its application to in vivo muscle metabolism measurement. The shot-noise limited SNR is derived and calculated to be 2 x104 for the physiological blood concentrations of muscle. Aiming at shot-noise limited SNR performance and fast imaging, we utilize sample and hold circuits to reduce high-frequency noise. These circuits have also been designed to be parallel integrating, through which SNR of 2 x103 and 2 Hz imaging acquisition rate have been achieved when the probe is placed on a muscle model. The noise corresponds to 2 x10-4 optical density error, which suggests an in vitro resolution of 15. 4 nM blood volume and 46.8 nM deoxygenation changes. A 48 dB digital gain control circuit with 256 steps is employed to enlarge the dynamic range of the imager. We utilize cuff ischemia as a living model demonstration and its results are reported. The instrument is applied during exercise to measure the changes of blood volume and deoxygenation, which provides important information about muscle metabolism. We find that the primary source of noise encountered during exercise experiment is from the random motion of muscle. The results demonstrate that the LED cw imager is ideal for the noninvasive study of muscle metabolism.

  16. Target volume geometric change and/or deviation from the cranium during fractionated stereotactic radiotherapy for brain metastases: potential pitfalls in image guidance based on bony anatomy alignment.

    Science.gov (United States)

    Ohtakara, Kazuhiro; Hoshi, Hiroaki

    2014-12-01

    This study sought to evaluate the potential geometrical change and/or displacement of the target relative to the cranium during fractionated stereotactic radiotherapy (FSRT) for treating newly developed brain metastases. For 16 patients with 21 lesions treated with image-guided frameless FSRT in 5 or 10 fractions using a 6-degree-of-freedom image guidance system-integrated platform, the unenhanced computed tomography or T2-weighted magnetic resonance images acquired until the completion of FSRT were fused to the planning image datasets for comparison. Significant change was defined as ≥3-mm change in the tumour diameter or displacement of the tumour centroid. FSRT was started 1 day after planning image acquisition. Tumour shrinkage, deviation and both were observed in 2, 1 and 1 of the 21 lesions, respectively, over a period of 7-13 days. Tumour shrinkage or deviation resulted in an increase or decrease in the marginal dose to the tumour, respectively, and a substantial increase in the irradiated volume for the surrounding tissue irrespective of the pattern of alteration. No obvious differences in the clinical and treatment characteristics were noted among the populations with or without significant changes in tumour volume or position. Target deformity and/or deviation can unexpectedly occur even during relatively short-course FSRT, inevitably leading to a gradual discrepancy between the planned and actually delivered doses to the tumour and surrounding tissue. To appropriately weigh the treatment outcome against the planned dose distribution, target deformity and/or deviation should also be considered in addition to the immobilisation accuracy, as image guidance with bony anatomy alignment does not necessarily guarantee accurate target localisation until completion of FSRT. © 2014 The Royal Australian and New Zealand College of Radiologists.

  17. Role of residual kidney function and convective volume on change in beta2-microglobulin levels in hemodiafiltration patients

    NARCIS (Netherlands)

    Penne, E. Lars; van der Weerd, Neelke C.; Blankestijn, Peter J.; van den Dorpel, Marinus A.; Grooteman, Muriel P. C.; Nubé, Menso J.; ter Wee, Piet M.; Lévesque, Renée; Bots, Michiel L.

    2010-01-01

    Removal of beta2-microglobulin (beta2M) can be increased by adding convective transport to hemodialysis (HD). The aim of this study was to investigate the change in beta2M levels after 6-mo treatment with hemodiafiltration (HDF) and to evaluate the role of residual kidney function (RKF) and the

  18. Role of residual kidney function and convective volume on change in β2-microglobulin levels in hemodiafiltration patients

    NARCIS (Netherlands)

    E.L. Penne (Lars); N.C. van der Weerd (Neelke); P.J. Blankestijn (Peter); M.A. van den Dorpel (Marinus); M.P.C. Grooteman (Muriel); M.J. Nubé (Menso); P.M. ter Wee (Piet); R. Lévesque (Renée); M.L. Bots (Michiel)

    2010-01-01

    textabstractBackground and objectives: Removal of β2-microglobulin (β2M) can be increased by adding convective transport to hemodialysis (HD). The aim of this study was to investigate the change in β2M levels after 6-mo treatment with hemodiafiltration (HDF) and to evaluate the role of residual

  19. Changes in plasma volume, in transcapillary escape rate of albumin and in subcutaneous blood flow during hypoglycaemia in man

    DEFF Research Database (Denmark)

    Hilsted, J; Bonde-Petersen, F; Madsbad, S

    1985-01-01

    and transcapillary escape rate increased significantly during hypoglycaemia. Skin temperature and local subcutaneous adipose tissue blood flow were measured in four different regions. Both tended to decrease during hypoglycaemia and decreased significantly 2 h after hypoglycaemia. There was no correlation between...... changes in the two measurements, suggesting that there is no simple relationship between subcutaneous blood flow and skin temperature during hypoglycaemia....

  20. Camera on vessel : A camera-based system to measure change in water volume in a drinking glass

    NARCIS (Netherlands)

    Ayoola, I.B.I.; Chen, W.; Feijs, L.M.G.

    2015-01-01

    A major problem related to chronic health is patients’ “compliance” with new lifestyle changes, medical prescriptions, recommendations, or restrictions. Heart-failure and hemodialysis patients are usually placed on fluid restrictions due to their hemodynamic status. A holistic approach to managing

  1. Bone marrow edema-like lesions change in volume in the majority of patients with osteoarthritis; associations with clinical features

    Energy Technology Data Exchange (ETDEWEB)

    Kornaat, Peter R.; Sharma, Ruby; Bloem, Johan L.; Watt, Iain [Leiden University Medical Center, Department of Radiology, Leiden (Netherlands); Kloppenburg, Margreet; Botha-Scheepers, Stella A. [Leiden University Medical Center, Department of Rheumatology, Leiden (Netherlands); Hellio le Graverand, Marie-Pierre [Pfizer Groton, Groton, CT (United States); Coene, L.N.J.E.M. [Haga Hospital, Department of Orthopaedic Surgery, The Hague (Netherlands)

    2007-12-15

    It has been suggested that bone marrow edema-like (BME) lesions in the knee are associated with progression of osteoarthritis (OA). The purpose of our study in patients with OA was to evaluate prospectively changes of BME lesions over 2 years and their relationship with clinical features. Magnetic resonance (MR) images of the knee were obtained from 182 patients (20% male; aged 43-76 years; mean age 59 years) who had been diagnosed with familial symptomatic OA at multiple joint sites. MR images were made at baseline and at 2 years follow-up. BME lesions in 2 years were associated with clinical features assessed by Western Ontario and McMaster Universities Osteoarthritis (WOMAC) scores. A total of 327 BME lesions were recorded. Total size of BME lesions changed in 90 patients (66%). Size of individual lesions changed in 147 foci (45%): new lesions appeared in 69 (21%), existing lesions disappeared in 32 (10%), increased in size in 26 (8%) and decreased in size in 20 (6%) lesions. Increase or decrease of BME lesions, over a 2-year time period, was not associated with severity of WOMAC scores. BME lesions fluctuated in the majority of patients with OA over a 2-year time period. These changes were not associated with severity of WOMAC scores at the study end point. (orig.)

  2. Bone marrow edema-like lesions change in volume in the majority of patients with osteoarthritis; associations with clinical features

    International Nuclear Information System (INIS)

    Kornaat, Peter R.; Sharma, Ruby; Bloem, Johan L.; Watt, Iain; Kloppenburg, Margreet; Botha-Scheepers, Stella A.; Hellio le Graverand, Marie-Pierre; Coene, L.N.J.E.M.

    2007-01-01

    It has been suggested that bone marrow edema-like (BME) lesions in the knee are associated with progression of osteoarthritis (OA). The purpose of our study in patients with OA was to evaluate prospectively changes of BME lesions over 2 years and their relationship with clinical features. Magnetic resonance (MR) images of the knee were obtained from 182 patients (20% male; aged 43-76 years; mean age 59 years) who had been diagnosed with familial symptomatic OA at multiple joint sites. MR images were made at baseline and at 2 years follow-up. BME lesions in 2 years were associated with clinical features assessed by Western Ontario and McMaster Universities Osteoarthritis (WOMAC) scores. A total of 327 BME lesions were recorded. Total size of BME lesions changed in 90 patients (66%). Size of individual lesions changed in 147 foci (45%): new lesions appeared in 69 (21%), existing lesions disappeared in 32 (10%), increased in size in 26 (8%) and decreased in size in 20 (6%) lesions. Increase or decrease of BME lesions, over a 2-year time period, was not associated with severity of WOMAC scores. BME lesions fluctuated in the majority of patients with OA over a 2-year time period. These changes were not associated with severity of WOMAC scores at the study end point. (orig.)

  3. Predictive and prognostic value of tumor volume and its changes during radical radiotherapy of stage III non-small cell lung cancer. A systematic review

    Energy Technology Data Exchange (ETDEWEB)

    Kaesmann, Lukas [University of Luebeck, Department of Radiation Oncology, Luebeck (Germany); Niyazi, Maximilian; Fleischmann, Daniel [LMU Munich, Department of Radiation Oncology, Munich (Germany); German Cancer Consortium (DKTK), partner site Munich, Munich (Germany); German Cancer Research Center (DKFZ), Heidelberg (Germany); Blanck, Oliver; Baumann, Rene [University Medical Center Schleswig-Holstein, Department of Radiation Oncology, Kiel (Germany); Baues, Christian; Klook, Lisa; Rosenbrock, Johannes; Trommer-Nestler, Maike [University Hospital of Cologne, Department of Radiotherapy, Cologne (Germany); Dobiasch, Sophie [Technische Universitaet Muenchen, Department of Radiation Oncology, Munich (Germany); Eze, Chukwuka [LMU Munich, Department of Radiation Oncology, Munich (Germany); Gauer, Tobias; Goy, Yvonne [University Medical Center Hamburg-Eppendorf, Department of Radiotherapy and Radio-Oncology, Hamburg (Germany); Giordano, Frank A.; Sautter, Lisa [University Medical Center Mannheim, Department of Radiation Oncology, Mannheim (Germany); Hausmann, Jan [University Medical Center Duesseldorf, Department of Radiation Oncology, Duesseldorf (Germany); Henkenberens, Christoph [Hannover Medical School, Department of Radiation and Special Oncology, Hannover (Germany); Kaul, David; Thieme, Alexander H. [Charite School of Medicine and University Hospital, Campus Virchow-Klinikum, Department of Radiation Oncology, Berlin (Germany); Krug, David; Schmitt, Daniela [University Hospital Heidelberg and National Center for Radiation Research in Oncology (NCRO) and Heidelberg Institute for Radiation Oncology (HIRO), Department of Radiation Oncology, Heidelberg (Germany); Maeurer, Matthias [University Medical Center Jena, Department of Radiation Oncology, Jena (Germany); Panje, Cedric M. [Kantonsspital St. Gallen, Department of Radiation Oncology, St. Gallen (Switzerland); Suess, Christoph [University Medical Center Regensburg, Department of Radiation Oncology, Regensburg (Germany); Ziegler, Sonia [University Medical Center Erlangen, Department of Radiation Oncology, Erlangen (Germany); Ebert, Nadja [University Medical Center Dresden, Department of Radiation Oncology, Dresden (Germany); OncoRay - National Center for Radiation Research in Oncology, Dresden (Germany); Medenwald, Daniel [Martin Luther University Halle-Wittenberg, Department of Radiation Oncology, Faculty of Medicine, Halle (Germany); Ostheimer, Christian [Martin Luther University Halle-Wittenberg, Department of Radiation Oncology, Faculty of Medicine, Halle (Germany); Klinik und Poliklinik fuer Strahlentherapie, Universitaetsklinikum Halle (Saale) (Germany); Collaboration: Young DEGRO Trial Group

    2018-02-15

    Lung cancer remains the leading cause of cancer-related mortality worldwide. Stage III non-small cell lung cancer (NSCLC) includes heterogeneous presentation of the disease including lymph node involvement and large tumour volumes with infiltration of the mediastinum, heart or spine. In the treatment of stage III NSCLC an interdisciplinary approach including radiotherapy is considered standard of care with acceptable toxicity and improved clinical outcome concerning local control. Furthermore, gross tumour volume (GTV) changes during definitive radiotherapy would allow for adaptive replanning which offers normal tissue sparing and dose escalation. A literature review was conducted to describe the predictive value of GTV changes during definitive radiotherapy especially focussing on overall survival. The literature search was conducted in a two-step review process using PubMed registered /Medline registered with the key words ''stage III non-small cell lung cancer'' and ''radiotherapy'' and ''tumour volume'' and ''prognostic factors''. After final consideration 17, 14 and 9 studies with a total of 2516, 784 and 639 patients on predictive impact of GTV, GTV changes and its impact on overall survival, respectively, for definitive radiotherapy for stage III NSCLC were included in this review. Initial GTV is an important prognostic factor for overall survival in several studies, but the time of evaluation and the value of histology need to be further investigated. GTV changes during RT differ widely, optimal timing for re-evaluation of GTV and their predictive value for prognosis needs to be clarified. The prognostic value of GTV changes is unclear due to varying study qualities, re-evaluation time and conflicting results. The main findings were that the clinical impact of GTV changes during definitive radiotherapy is still unclear due to heterogeneous study designs with varying quality

  4. Modificações do volume e da histologia de focos de endometriose em ratas tratadas com sinvastatina Changes in the volume and histology of focus of endometriosis in rats treated with sinvastatin

    Directory of Open Access Journals (Sweden)

    João Nogueira Neto

    2007-08-01

    Full Text Available OBJETIVO: analisar alterações macroscópicas e histológicas que ocorrem com o uso da sinvastatina em endometriose experimental em ratas. MÉTODOS: quarenta ratas da linhagem Wistar foram submetidas à técnica de autotransplante uterino em mesentério. Após três semanas, 24 ratas desenvolveram endometriose experimental grau III e foram divididas em dois grupos: Sinvastatina (dado 20 mg/kg/dia via oral e Controle (dado cloreto de sódio a 0,9% na quantidade de 1 mL/100 g de peso corpóreo via oral, que receberam gavagem durante 14 dias seguido de morte. Os volumes dos implantes foram calculados [4pi (comprimento/2 x (largura/2 x (altura/2/3] nas intervenções cirúrgicas e após a morte dos animais. Os autotransplantes foram retirados, corados com a hematoxilina-eosina e analisados à microscopia de luz. Foram usados o teste de Mann-Whitney para amostras independentes e o teste de Wilcoxon para amostras relacionadas. Para avaliação histológica, foi usado o teste exato de Fisher, adotando-se nível de significância de 5%. RESULTADOS: a diferença entre os volumes médios iniciais dos autotransplantes nos dois grupos foi insignificante (p=1,00, e, entre os volumes médios finais, significante (p=0,04. Houve aumento significativo (p=0,01 entre os volumes médios iniciais e finais do Grupo Controle e redução insignificante no Grupo Sinvastatina (p=0,95. Histologicamente (p=0,64, o Grupo Sinvastatina (n=9 mostrou a parede epitelial moderadamente preservada em sete casos (77,80% e dois casos com camada epitelial bem preservada (22,2%, e o Grupo Controle (n=12 com sete casos (58,30% moderadamente preservados e cinco casos (41,70% bem preservados. CONCLUSÕES: a sinvastatina impediu o crescimento dos focos de endometriose experimental. São promissores os estudos com uso da sinvastatina por período mais prolongado.PURPOSE: to analyze the macroscopic and histological changes that occur with the use of sinvastatin in experimental endometriosis

  5. Positron annihilation lifetime studies of changes in free volume on some biorelevant nitrogen heterocyclic compounds and their S-glycosylation

    International Nuclear Information System (INIS)

    Mahmoud, K.R.; Khodair, A.I.; Shaban, S.Y.

    2015-01-01

    A series of N-heterocyclic compounds was investigated by positron annihilation lifetime spectroscopy as well as Doppler broadening of annihilation radiation (DBAR) at room temperature. The results showed that the formation probability and life time of ortho-positronium in this series are structure and electron-donation character dependent, and can give more information about the structure. The DBAR provides direct information about the change of core and valance electrons as well as the number of defect types present in these compounds. - Highlights: • N-heterocyclic compounds were studied by PALS and DBAR at room temperature. • These compounds contain thiohydantoins which have wide applications as anticarcinogenic, antiviral, human immunodeficiency virus (HIV) and antimicrobial activity. • The DBAR provides direct information about the change of core and valance electrons as well as the number of defect types present in these compounds.

  6. Quantification of gross tumour volume changes between simulation and first day of radiotherapy for patients with locally advanced malignancies of the lung and head/neck.

    Science.gov (United States)

    Kishan, Amar U; Cui, Jing; Wang, Pin-Chieh; Daly, Megan E; Purdy, James A; Chen, Allen M

    2014-10-01

    To quantify changes in gross tumour volume (GTV) between simulation and initiation of radiotherapy in patients with locally advanced malignancies of the lung and head/neck. Initial cone beam computed tomography (CT) scans from 12 patients with lung cancer and 12 with head/neck cancer (head and neck squamous cell carcinoma (HNSCC)) treated with intensity-modulated radiotherapy with image guidance were rigidly registered to the simulation CT scans. The GTV was demarcated on both scans. The relationship between percent GTV change and variables including time interval between simulation and start, tumour (T) stage, and absolute weight change was assessed. For lung cancer patients, the GTV increased a median of 35.06% (range, -16.63% to 229.97%) over a median interval of 13 days (range, 7-43), while for HNSCC patients, the median GTV increase was 16.04% (range, -8.03% to 47.41%) over 13 days (range, 7-40). These observed changes are statistically significant. The magnitude of this change was inversely associated with the size of the tumour on the simulation scan for lung cancer patients (P lung cancer cases) did not correlate with degree of GTV change (P > 0.1). While the observed changes in GTV were moderate from the time of simulation to start of radiotherapy, these findings underscore the importance of image guidance for target localisation and verification, particularly for smaller tumours. Minimising the delay between simulation and treatment initiation may also be beneficial. © 2014 The Royal Australian and New Zealand College of Radiologists.

  7. Correlation between left ventricular diastolic function before and after valve replacement surgery and myocardial ultrastructural changes in patients with left ventricular volume-overloaded valvular heart diseases

    International Nuclear Information System (INIS)

    Okada, Tomiro

    1993-01-01

    Left ventricular (LV) diastolic functions in 23 patients with aortic regurgitation (AR) and 22 patients with mitral regurgitation (MR) were evaluated by gated blood pool scintigraphy. LV myocardial biopsy was performed during open heart surgery, and LV myocardial ultrastructural changes were evaluated by electron microscope. Correlation between LV diastolic function and myocardial ultrastructural changes was examined. It was suggested that preoperative LV diastolic dysfunction occurred earlier than LV systolic dysfunction in patients with AR and MR. LV early diastolic dysfunction was especially significant in patients with AR. LV systolic function was significantly improved postoperatively compared with LV diastolic function in patients with AR and MR. It was suggested that LV interstitial fibrosis caused LV diastolic dysfunction in patients with AR and MR, and insufficiency of myocardial thickening as compensation in patients with MR. It was presumed that LV diastolic dysfunction was irreversible in patients with AR and MR in the distant postoperative period due to persistence of the preoperative myocardial ultrastructural change, e.g., interstitial fibrosis. These LV diastolic indices measured by gated pool scintigraphy were useful in predicting LV ultrastructural changes and postoperative LV dysfunction in patients with LV volume-overloaded valvular heart disease. (author)

  8. Positron annihilation lifetime studies of changes in free volume on some biorelevant nitrogen heterocyclic compounds and their S-glycosylation.

    Science.gov (United States)

    Mahmoud, K R; Khodair, A I; Shaban, S Y

    2015-11-01

    A series of N-heterocyclic compounds was investigated by positron annihilation lifetime spectroscopy as well as Doppler broadening of annihilation radiation (DBAR) at room temperature. The results showed that the formation probability and life time of ortho-positronium in this series are structure and electron-donation character dependent, and can give more information about the structure. The DBAR provides direct information about the change of core and valance electrons as well as the number of defect types present in these compounds. Copyright © 2015 Elsevier Ltd. All rights reserved.

  9. Evaluation of volume change in rectum and bladder during application of image-guided radiotherapy for prostate carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Luna, J. A., E-mail: yosimoon13@hotmail.com [Departamento de Física, Universidad Nacional de Costa Rica, Heredia (Costa Rica); Rojas, J. I., E-mail: isaac.rojas@siglo21.cr [Centro Médico Radioterapia Siglo XX1, La Uruca (Costa Rica); PROXTRONICS CR, Ltda, Heredia (Costa Rica)

    2016-07-07

    All prostate cancer patients from Centro Médico Radioterapia Siglo XXI receive Volumetric Modulated Arc Therapy (VMAT). This therapy uses image-guided radiotherapy (IGRT) with the Cone Beam Computed Tomography (CBCT). This study compares the planned dose in the reference CT image against the delivered dose recalculate in the CBCT image. The purpose of this study is to evaluate the anatomic changes and related dosimetric effect based on weekly CBCT directly for patients with prostate cancer undergoing volumetric modulated arc therapy (VMAT) treatment. The collected data were analyzed using one-way ANOVA.

  10. Glacier area and volume changes of Hidden Valley, Mustang, Nepal from ~1980s to 2010 based on remote sensing

    Directory of Open Access Journals (Sweden)

    L. Lama

    2015-05-01

    Full Text Available Glaciers are one of the important natural resources of freshwater and sources of water for hydropower, agriculture and drinking whenever the water is scarce. This mapping and change analysis helps to understand the status and decadal changes of glaciers in Hidden Valley, Mustang district, Nepal. The investigation is carried out using Landsat images of the years 1977 (~1980s, 1990, 2000 and 2010. We mapped 10 glaciers of the Hidden Valley covering an area of 19.79 km2 based on the object-based image classification method using an automatic method and manual delineation by a Geographic Information System (GIS, separately. The glacier outlines for 2010, 2000, 1990 and 1980s in both methods are delineated from the multispectral Landsat images of the respective years. The total area losses of the glaciers from the automatic method are 1.713 and 0.625 km2 between 1990−2000 and 2000−2010 and from manual delineation are 2.021, 1.264, 1.041 km2 between ~1980s−1990, 1990−2000 and 2000−2010. The amount of average estimated glacier ice reserves lost is 0.326 km3 (26.26 % and the total glacier area loss is 4.33 km2 (21.87 % from the 1980s to 2010 based on manual delineation. The glaciers of Hidden Valley are shrinking and fragmented due to decrease in glacier area and ice reserves.

  11. Endotracheal tube and laryngeal mask airway cuff volume changes with altitude: a rule of thumb for aeromedical transport.

    Science.gov (United States)

    Mann, Catherine; Parkinson, Neil; Bleetman, Anthony

    2007-03-01

    Helicopters and light (unpressurised) aircraft are used increasingly for the transport of ventilated patients. Most of these patients are ventilated through endotracheal tubes (ETTs), others through laryngeal mask airways (LMAs). The cuffs of both ETTs and LMAs inflate with increases in altitude as barometric pressure decreases (30 mbar/1000 feet). Tracheal mucosa perfusion becomes compromised at a pressure of approximately 30 cm H2O; critical perfusion pressure is 50 cm H2O. The change in dimensions of the inflated cuffs of a size 8 ETT and a size 5 LMA were measured with digital callipers at 1000 feet intervals in the unpressurised cabin of an Agusta 109 helicopter used by the Warwickshire and Northamptonshire Air Ambulance. A linear expansion in cuff dimensions as a function of altitude increase was identified. For ETTs, a formula for removal of air from the cuff with increasing altitude was calculated and is recommended for use in aeromedical transfers. This is 1/17x1.1 = 0.06 ml/1000 foot ascent/ml initial cuff inflation. The data for LMA cuff expansion failed to show significant correlation with altitude change. Further work is required to determine a similar rule of thumb for LMA cuff deflation.

  12. Revised shallow and deep water-level and storage-volume changes in the Equus Beds Aquifer near Wichita, Kansas, predevelopment to 1993

    Science.gov (United States)

    Hansen, Cristi V.; Lanning-Rush, Jennifer L.; Ziegler, Andrew C.

    2013-01-01

    credits from the Equus Beds aquifer by the city of Wichita. The 1993 water levels correspond to the lowest recorded levels and largest storage declines since 1940. Revised and new water-level maps of shallow and deep layers were developed to better represent the general condition of the aquifer. Only static water levels were used to better represent the general condition of the aquifer and comply with Wichita’s ASR permits. To ensure adequate data density, the January 1993 period was expanded to October 1992 through February 1993. Static 1993 water levels from the deep aquifer layer of the Equus Beds aquifer possibly could be used as the lower baseline for regulatory purposes. Previously, maps of water-level changes used to estimate the storage-volume changes included a combination of static (unaffected by pumping or nearby pumping) and stressed (affected by pumping or nearby pumping) water levels from wells. Some of these wells were open to the shallow aquifer layer and some were open to the deep aquifer layer of the Equus Beds aquifer. In this report, only static water levels in the shallow aquifer layer were used to determine storage-volume changes. The effects on average water-level and storage-volume change from the use of mixed, stressed water levels and a specific yield of 0.20 were compared to the use of static water levels in the shallow aquifer and a specific yield of 0.15. This comparison indicates that the change in specific yield causes storage-volume changes to decrease about 25 percent, whereas the use of static water levels in the shallow aquifer layer causes an increase of less than 4 percent. Use of a specific yield of 0.15 will result in substantial decreases in the amount of storage-volume change compared to those reported previously that were calculated using a specific yield of 0.20. Based on these revised water-level maps and computations, the overall decline and change in storage from predevelopment to 1993 represented a loss in storage of about

  13. A pilot study to monitor changes in spirometry and lung volume, following an exacerbation of Chronic Obstructive Pulmonary Disease (COPD), as part of a supported discharge program.

    Science.gov (United States)

    Cushen, Breda; McCormack, Niamh; Hennigan, Kerrie; Sulaiman, Imran; Costello, Richard W; Deering, Brenda

    2016-10-01

    One-third of patients with an exacerbation of Chronic Obstructive Pulmonary Disease(COPD) are re-hospitalised at 90 days. Exacerbation recovery is associated with reductions in lung hyperinflation and improvements in symptoms and physical activity. We assessed the feasibility of monitoring these clinical parameters in the home. We hypothesised that the degree of change in spirometry and lung volumes differs between those who had an uneventful recovery and those who experienced a further exacerbation. Hospitalised patients with an acute exacerbation of COPD referred for a supported discharge program participated in the study. Spirometry and Inspiratory Vital Capacity(IVC) were measured in the home at Days 1, 14 and 42 post-discharge. Patients also completed Medical Research Council(MRC), Borg and COPD Assessment Test(CAT) scores and were provided with a tri-axial accelerometer. Any new exacerbation events were recorded. Sixty-five patients with 72 exacerbation episodes were recruited. Fifty percent experienced a second exacerbation. Adequate IVC measurements were achieved by 90%, while only 70% completed spirometry. Uneventful recovery was accompanied by significant improvements in physiological measurements at day14, improved symptom scores and step count, p volumes, symptoms and step count following a COPD exacerbation may help to identify patients at risk of re-exacerbation. It is feasible to carry out these assessments in the home as part of a supported discharge programme. Copyright © 2016 Elsevier Ltd. All rights reserved.

  14. Change in volume parameters induced by neoadjuvant chemotherapy provide accurate prediction of overall survival after resection in patients with oesophageal cancer

    Energy Technology Data Exchange (ETDEWEB)

    Tamandl, Dietmar; Fueger, Barbara; Kinsperger, Patrick; Haug, Alexander; Ba-Ssalamah, Ahmed [Medical University of Vienna, Department of Biomedical Imaging and Image-Guided Therapy, Comprehensive Cancer Center GET-Unit, Vienna (Austria); Gore, Richard M. [University of Chicago Pritzker School of Medicine, Department of Radiology, Chicago, IL (United States); Hejna, Michael [Medical University of Vienna, Department of Internal Medicine, Division of Medical Oncology, Comprehensive Cancer Center GET-Unit, Vienna (Austria); Paireder, Matthias; Schoppmann, Sebastian F. [Medical University of Vienna, Department of Surgery, Upper-GI-Service, Comprehensive Cancer Center GET-Unit, Vienna (Austria)

    2016-02-15

    To assess the prognostic value of volumetric parameters measured with CT and PET/CT in patients with neoadjuvant chemotherapy (NACT) and resection for oesophageal cancer (EC). Patients with locally advanced EC, who were treated with NACT and resection, were retrospectively analysed. Data from CT volumetry and {sup 18} F-FDG PET/CT (maximum standardized uptake [SUVmax], metabolic tumour volume [MTV], and total lesion glycolysis [TLG]) were recorded before and after NACT. The impact of volumetric parameter changes induced by NACT (MTV{sub RATIO}, TLG{sub RATIO}, etc.) on overall survival (OS) was assessed using a Cox proportional hazards model. Eighty-four patients were assessed using CT volumetry; of those, 50 also had PET/CT before and after NACT. Low post-treatment CT volume and thickness, MTV, TLG, and SUVmax were all associated with longer OS (p < 0.05), as were CTthickness{sub RATIO}, MTV{sub RATIO}, TLG{sub RATIO}, and SUVmax{sub RATIO} (p < 0.05). In the multivariate analysis, only MTV{sub RATIO} (Hazard ratio, HR 2.52 [95 % Confidence interval, CI 1.33-4.78], p = 0.005), TLG{sub RATIO} (HR 3.89 [95%CI 1.46-10.34], p = 0.006), and surgical margin status (p < 0.05), were independent predictors of OS. MTV{sub RATIO} and TLG{sub RATIO} are independent prognostic factors for survival in patients after NACT and resection for EC. (orig.)

  15. Buoyancy Effect of Ionic Vacancy on the Change of the Partial Molar Volume in Ferricyanide-Ferrocyanide Redox Reaction under a Vertical Gravity Field

    Directory of Open Access Journals (Sweden)

    Yoshinobu Oshikiri

    2013-01-01

    Full Text Available With a gravity electrode (GE in a vertical gravity field, the buoyancy effect of ionic vacancy on the change of the partial molar volume in the redox reaction between ferricyanide (FERRI and ferrocyanide (FERRO ions was examined. The buoyancy force of ionic vacancy takes a positive or negative value, depending on whether the rate-determining step is the production or extinction of the vacancy. Though the upward convection over an upward electrode in the FERRO ion oxidation suggests the contribution of the positive buoyancy force arising from the vacancy production, the partial molar volume of the vacancy was not measured. On the other hand, for the downward convection under a downward electrode in the FERRI ion reduction, it was not completely but partly measured by the contribution of the negative buoyancy force from the vacancy extinction. Since the lifetime of the vacancy is decreased by the collision between ionic vacancies during the convection, the former result was ascribed to the shortened lifetime due to the increasing collision efficiency in the enhanced upward convection over an upward electrode, whereas the latter was thought to arise from the elongated lifetime due to the decreasing collision efficiency by the stagnation under the downward electrode.

  16. Neurobiological changes of schizotypy: evidence from both volume-based morphometric analysis and resting-state functional connectivity.

    Science.gov (United States)

    Wang, Yi; Yan, Chao; Yin, Da-zhi; Fan, Ming-xia; Cheung, Eric F C; Pantelis, Christos; Chan, Raymond C K

    2015-03-01

    The current study sought to examine the underlying brain changes in individuals with high schizotypy by integrating networks derived from brain structural and functional imaging. Individuals with high schizotypy (n = 35) and low schizotypy (n = 34) controls were screened using the Schizotypal Personality Questionnaire and underwent brain structural and resting-state functional magnetic resonance imaging on a 3T scanner. Voxel-based morphometric analysis and graph theory-based functional network analysis were conducted. Individuals with high schizotypy showed reduced gray matter (GM) density in the insula and the dorsolateral prefrontal gyrus. The graph theoretical analysis showed that individuals with high schizotypy showed similar global properties in their functional networks as low schizotypy individuals. Several hubs of the functional network were identified in both groups, including the insula, the lingual gyrus, the postcentral gyrus, and the rolandic operculum. More hubs in the frontal lobe and fewer hubs in the occipital lobe were identified in individuals with high schizotypy. By comparing the functional connectivity between clusters with abnormal GM density and the whole brain, individuals with high schizotypy showed weaker functional connectivity between the left insula and the putamen, but stronger connectivity between the cerebellum and the medial frontal gyrus. Taken together, our findings suggest that individuals with high schizotypy present changes in terms of GM and resting-state functional connectivity, especially in the frontal lobe. © The Author 2014. Published by Oxford University Press on behalf of the Maryland Psychiatric Research Center. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  17. Understanding and Improvement of an Experiment Measuring Chemical Reaction Rates by Monitoring Volume Change of a Gas: On the Reaction between HCl(aq) and Mg(s)

    International Nuclear Information System (INIS)

    Bang, Jeong Ah; Yoon, Hee Sook; Jeong, Dae Hong; Choi, Won Ho

    2006-01-01

    In this study we analyzed and improved an experiment measuring chemical reaction rates introduced in the high school science textbooks through an understanding of the phenomena observed in carrying out the experiment. For this purpose, the contents of textbooks related to the experiment were analyzed, and the problems observed in carrying out the experiment were addressed through experimental analysis. When the experiment was carried out by the method of aquatic transposition presented in textbooks, the observed volume change of H 2 gas was delayed and chemical reaction rate was increased in the early stage of reaction period. To resolve these problems, an improved method for measuring the reaction rates was suggested. In the improved experiment the reaction rate was measured to be constant on time, which was interpreted in terms of the concentration of H + and the surface area of magnesium

  18. Intrinsic optical signal imaging of the blood volume changes is sufficient for mapping the resting state functional connectivity in the rodent cortex

    Science.gov (United States)

    Kura, Sreekanth; Xie, Hongyu; Fu, Buyin; Ayata, Cenk; Boas, David A.; Sakadžić, Sava

    2018-06-01

    Objective. Resting state functional connectivity (RSFC) allows the study of functional organization in normal and diseased brain by measuring the spontaneous brain activity generated under resting conditions. Intrinsic optical signal imaging (IOSI) based on multiple illumination wavelengths has been used successfully to compute RSFC maps in animal studies. The IOSI setup complexity would be greatly reduced if only a single wavelength can be used to obtain comparable RSFC maps. Approach. We used anesthetized mice and performed various comparisons between the RSFC maps based on single wavelength as well as oxy-, deoxy- and total hemoglobin concentration changes. Main results. The RSFC maps based on IOSI at a single wavelength selected for sensitivity to the blood volume changes are quantitatively comparable to the RSFC maps based on oxy- and total hemoglobin concentration changes obtained by the more complex IOSI setups. Moreover, RSFC maps do not require CCD cameras with very high frame acquisition rates, since our results demonstrate that they can be computed from the data obtained at frame rates as low as 5 Hz. Significance. Our results will have general utility for guiding future RSFC studies based on IOSI and making decisions about the IOSI system designs.

  19. Volume Change and Liver Parenchymal Signal Intensity in Gd-EOB-DTPA-Enhanced Magnetic Resonance Imaging after Portal Vein Embolization prior to Hepatectomy

    Directory of Open Access Journals (Sweden)

    Ayako Akiba

    2014-01-01

    Full Text Available Purpose. To investigate the liver volume change and the potential of early evaluation by contrast-enhanced magnetic resonance imaging (MRI using gadolinium-ethoxybenzyl-diethylenetriamine pentaacetic acid (Gd-EOB-DTPA after portal vein embolization (PVE. Materials and Methods. Retrospective evaluations of computed tomography (CT volumetry of total liver and nonembolized areas were performed before and 3 weeks after PVE in 37 cases. The percentage of future liver remnant (%FLR and the change ratio of %FLR (%FLR ratio were calculated. Prospective evaluation of signal intensities (SIs was performed to estimate the role of Gd-EOB-DTPA-enhanced MRI as a predictor of hypertrophy in 16 cases. The SI contrast between embolized and nonembolized areas was calculated 1 week after PVE. The change in SI contrast before and after PVE (SI ratio was also calculated in 11 cases. Results. %FLR ratio significantly increased, and SI ratio significantly decreased (both P<0.01. There were significant negative correlations between %FLR and SI contrast and between %FLR and SI ratio (both P<0.01. Conclusion. Hypertrophy in the nonembolized area after PVE was indicated by CT volumetry, and measurement of SI contrast and SI ratio in Gd-EOB-DTPA-enhanced MRI early after PVE may be useful to predict the potential for hepatic hypertrophy.

  20. 'klima:aktiv energieeffiziente betriebe' (climate:active energy efficient companies) - the Austrian climate change program for industry. Volume 1

    International Nuclear Information System (INIS)

    Sattler, Peter; Sampl, Martin; Fuchsberger, Karin

    2007-01-01

    'klima:aktiv' is the climate change program of the Austrian Federal Ministry of Agriculture, Forestry, Environment and Water Management. The aim of 'klima:aktiv' is to reduce CO 2 emissions as well as reinforce renewable energy in Austria. To achieve these goals more than 20 programs for renewable energies and energy efficiency were created - 'energy efficient companies' being one of them. 'klima:aktiv' was created in order to identify and furthermore realise energy saving and CO 2 reducing measures. To build an active and effective network, regional programs, local consultants and companies on the energy-market are encouraged to become partners of the program to be multipliers.One focus of the program is the support of consultants which are acting as mediators to the companies. A step by step model was developed for companies to help them realise the goals of the program. To ensure the highest service efficiency from the first contact with companies, consultants were furthermore provided with special 'k:a eeb Pro-Tools', which include a wide variety of tools from analysis and development to financing advise.The program started in October 2005. Its mission statement for the first year was to reduce CO 2 emission at 45.000 t or 60 GWh of primarily electrical energy. To reach this goal, single regional agencies were committed to individual objectives. After one year, a detailed evaluation of the program was carried out with the aim to show the areas of success but also to highlight areas that will need adjustments for optimal results

  1. Impact of HPV testing, HPV vaccine development, and changing screening frequency on national Pap test volume: projections from the National Health Interview Survey (NHIS).

    Science.gov (United States)

    Eltoum, Isam A; Roberson, Janie

    2007-02-25

    The frequently cited number of 50 million annual Papanicolaou cervical screening (Pap) tests performed in the US was based on the National Health Interview Survey (NHIS) of the 1980s. Since then, monumental changes have occurred. More change will soon follow when primary human papilloma virus (HPV) testing and/or HPV vaccine delivery are fully accepted and implemented. The objectives of this study were 1) to estimate the total annual Pap tests performed in the US based on recent NHIS surveys, and 2) to estimate the potential change in the total annual Pap volume produced by changing demographics, reduced screening frequency, HPV testing, and the HPV vaccine. In the NHIS 2000 and NHIS 2005, women were asked to report the frequency of their Pap tests for the 6 years prior to the interview and to report whether they had abnormal findings. The authors analyzed the survey respondents answers to these questions by using SAS Survey Procedures (SAS Institute, NC). The results were stratified by age, and the total national volume was then extrapolated from a similarly stratified 2000 US census. The projected increase of total Pap tests for the next 25 years was determined by using the projected census data. Potential reductions of Pap tests performed secondarily to HPV testing of women >30 years old and of HPV vaccination were also determined. Based on NHIS 2000 and NHIS 2005, 66 million (95% CI, 65-68) and 65 million (95% CI, 64-67) Pap tests were performed in the US, respectively. Had HPV testing been performed in women older than 30 years who had both negative HPV and negative 3-year Pap tests, then 30% (95% CI, 29-32%) of Pap tests would not have been performed. If both HPV testing and vaccination are performed, the total number of Pap tests performed annually is predicted to be reduced by 43% (95% CI, 35-38%). Therefore, despite an expected increase in the population of women eligible for Pap tests, the total number will likely decrease substantially in the future

  2. The analysis of correlation between changes of myocardial enzymes level in serum before and after radiation and dose-volume histogram parameters of the heart

    International Nuclear Information System (INIS)

    Ding Xiuping; Li Hongjun; Li Baosheng; Wang Dongqing

    2012-01-01

    Objective: To analyze the correlation between the changes of myocardial enzyme level in serum before and after radiotherapy and dose - volume histogram (DVH) parameters of the heart. Methods: A total of 102 patients with 68 cases of lung cancer and 34 cases of esophageal cancer were recruited. All patients received three-dimensional conformal radiotherapy (3DCRT) or intensity-modulated radiotherapy (IMRT), with the radiation beams passing through the heart. Aspartate aminotransferase (AST), creatine kinase (CK), creatine kinase isozyme (CK-MB), lactate dehydrogenase (LDH), α-hydroxybutyrate dehydrogenase (α-HBDH) were determined in the serum before and after radiotherapy. All the enzyme levels before and after radiotherapy were compared through paired t-test. Independent sample t-test was conducted between sub-groups. And the dose-volume histogram (DVH) parameters of the heart were calculated (the volume percentage of heart receiving dose equal to or exceeding x Gy (V x ). The correlation between myocardial enzyme level and DVH parameters was analyzed through Pearson method. Results: Serum AST, CK-MB, LDH, α-HBDH levels increased significantly after radiotherapy (19.42: 27.89, 14.72:19.57, 178.80 : 217.57, 140.32 : 176.25, t =-3.39 - -6.92, all P=0.000). In Group IMRT, significant correlations between the increase of myocardial enzyme concentration and DVH parameters of the heart are found, AST with V 20 , V 25 , V 30 of heart ( r=0.302 - 0.431, P =0.039 - 0.003), CK with V 30 of heart (r=0.345, P=0.013), and CK-MB, LDH, α-HBDH with V 25 , V 30 (r=0.465 -0.376, P=0.001-0.005). In Group CRT, there are significant correlations between changes of CK-MB, LDH level and V 30 of heart (r =0.330, 0.274, P=0.014, 0.033), α-HBDH and V 25 , V 30 , and V 35 of heart (r=0.270-0.331, P=0.046-0.014). When the irradiation dose was more than 50 Gy, significant correlations were found between the concentration changes of AST, LDH, α-HBDH and V 25 , V 30 of heart (r=0

  3. Effect of Climate Change on Service Life of High Volume Fly Ash Concrete Subjected to Carbonation—A Korean Case Study

    Directory of Open Access Journals (Sweden)

    Ki-Bong Park

    2017-01-01

    Full Text Available The increase in CO2 concentrations and global warming will increase the carbonation depth of concrete. Furthermore, temperature rise will increase the rate of corrosion of steel rebar after carbonation. On the other hand, compared with normal concrete, high volume fly ash (HVFA concrete is more vulnerable to carbonation-induced corrosion. Carbonation durability design with climate change is crucial to the rational use of HVFA concrete. This study presents a probabilistic approach that predicts the service life of HVFA concrete structures subjected to carbonation-induced corrosion resulting from increasing CO2 concentrations and temperatures. First, in the corrosion initiation stage, a hydration-carbonation integration model is used to evaluate the contents of the carbonatable material, porosity, and carbonation depth of HVFA concrete. The Monte Carlo method is adopted to determine the probability of corrosion initiation. Second, in the corrosion propagation stage, an updated model is proposed to evaluate the rate of corrosion, degree of corrosion for cover cracking of concrete, and probability of corrosion cracking. Third, the whole service life is determined considering both corrosion initiation stage and corrosion propagation stage. The analysis results show that climate change creates a significant impact on the service life of durable concrete.

  4. A radiocardiographic method for continuous registration of cardiac and pulmonary blood volume changes during exercise in normals, athlets and patients with latent cardiac insufficiency

    International Nuclear Information System (INIS)

    Hoeck, A.; Hoeck, A.; Vyska, K.; Freundlieb, C.; Feinendegen, L.E.

    1978-01-01

    Radiocardiographic methods thus far measure transit times, ejection fractions and ventricular wall motion. In the present study a method is described that permits continuous registration of exercise induced changes of cardiac and pulmonary volume and their ratio. 12 normal individuals, 15 athlets and 6 patients with latent cardiac insufficiency received i.v. 2-3 mCi 99m-Tc-Albumin. Fast serial scintigrams were taken in AP projection of the chest for 5 minutes at rest, during 5 minutes of graded exercise and 5 minutes rest again. The ROIs were the entire heart and left upper lung. The athlets showed, compared to normals, an exercise induced increase of the pulmonary counting rates and a decrease of the cardiac counting rates; the opposite phenomen was observed in patients with latent cardiac insufficiency. The ratio of the two counting rates amplyfied the signal of deviation. The method is simple, safe and highly sensitive for measuring changes in cardio-pulmonary hemodynamics. (author)

  5. Pulmonary Perfusion Changes as Assessed by Contrast-Enhanced Dual-Energy Computed Tomography after Endoscopic Lung Volume Reduction by Coils.

    Science.gov (United States)

    Lador, Frédéric; Hachulla, Anne-Lise; Hohn, Olivia; Plojoux, Jérôme; Ronot, Maxime; Montet, Xavier; Soccal, Paola M

    2016-01-01

    Endoscopic lung volume reduction by coils (LVRC) is a recent treatment approach for severe emphysema. Furthermore, dual-energy computed tomography (DECT) now offers a combined assessment of lung morphology and pulmonary perfusion. The aim of our study was to assess the impact of LVRC on pulmonary perfusion with DECT. Seventeen patients (64.8 ± 6.7 years) underwent LVRC. DECT was performed prior to and after LVRC. For each patient, lung volumes and emphysema quantification were automatically calculated. Then, 6 regions of interest (ROIs) on the iodine perfusion map were drawn in the anterior, mid, and posterior right and left lungs at 4 defined levels. The ROI values were averaged to obtain lung perfusion as assessed by the lung's iodine concentration (CLung, μg·cm-3). The CLung values were normalized using the left atrial iodine concentration (CLA) to take into account differences between successive DECT scans. The 6-min walk distance (6MWD) improved significantly after the procedure (p = 0.0002). No lung volume changes were observed between successive DECT scans for any of the patients (p = 0.32), attesting the same suspended inspiration. After LVRC, the emphysema index was significantly reduced in the treated lung (p = 0.0014). Lung perfusion increased significantly adjacent to the treated areas (CLung/CLA from 3.4 ± 1.7 to 5.6 ± 2.2, p < 0.001) and in the ipsilateral untreated areas (from 4.1 ± 1.4 to 6.6 ± 1.7, p < 0.001), corresponding to a mean 65 and 61% increase in perfusion, respectively. No significant difference was observed in the contralateral upper and lower areas (from 4.4 ± 1.9 to 4.8 ± 2.1, p = 0.273, and from 4.9 ± 2.0 to 5.2 ± 1.7, p = 0.412, respectively). A significant correlation between increased 6MWD and increased perfusion was found (p = 0.0027, R2 = 0.3850). Quantitative analysis based on DECT acquisition revealed that LVRC results in a significant increase in perfusion in the coil-free areas adjacent to the treated ones, as

  6. Brain Tissue Volumes and Perfusion Change with the Number of Optic Neuritis Attacks in Relapsing Neuromyelitis Optica: A Voxel-Based Correlation Study.

    Directory of Open Access Journals (Sweden)

    Carlos A Sánchez-Catasús

    Full Text Available Recent neuroimaging studies show that brain abnormalities in neuromyelitis optica (NMO are more frequent than earlier described. Yet, more research considering multiple aspects of NMO is necessary to better understand these abnormalities. A clinical feature of relapsing NMO (RNMO is that the incremental disability is attack-related. Therefore, association between the attack-related process and neuroimaging might be expected. On the other hand, the immunopathological analysis of NMO lesions has suggested that CNS microvasculature could be an early disease target, which could alter brain perfusion. Brain tissue volume changes accompanying perfusion alteration could also be expected throughout the attack-related process. The aim of this study was to investigate in RNMO patients, by voxel-based correlation analysis, the assumed associations between regional brain white (WMV and grey matter volumes (GMV and/or perfusion on one side, and the number of optic neuritis (ON attacks, myelitis attacks and/or total attacks on the other side. For this purpose, high resolution T1-weighted MRI and perfusion SPECT imaging were obtained in 15 RNMO patients. The results showed negative regional correlations of WMV, GMV and perfusion with the number of ON attacks, involving important components of the visual system, which could be relevant for the comprehension of incremental visual disability in RNMO. We also found positive regional correlation of perfusion with the number of ON attacks, mostly overlapping the brain area where the WMV showed negative correlation. This provides evidence that brain microvasculature is an early disease target and suggests that perfusion alteration could be important in the development of brain structural abnormalities in RNMO.

  7. Gastric Fluid Volume Change After Oral Rehydration Solution Intake in Morbidly Obese and Normal Controls: A Magnetic Resonance Imaging-Based Analysis.

    Science.gov (United States)

    Shiraishi, Toshie; Kurosaki, Dai; Nakamura, Mitsuyo; Yazaki, Taiji; Kobinata, Satomi; Seki, Yosuke; Kasama, Kazunori; Taniguchi, Hideki

    2017-04-01

    Although preoperative fluid intake 2 hours before anesthesia is generally considered safe, there are concerns about delayed gastric emptying in obese subjects. In this study, the gastric fluid volume (GFV) change in morbidly obese subjects was investigated after ingesting an oral rehydration solution (ORS) and then compared with that in nonobese subjects. GFV change over time after the ingestion of 500 mL of ORS containing 2.5% carbohydrate (OS-1) was measured in 10 morbidly obese subjects (body mass index [BMI], >35) scheduled for bariatric surgery and 10 nonobese (BMI, 19-24) using magnetic resonance imaging. After 9 hours of fasting, magnetic resonance imaging scans were performed at preingestion, 0 min (just after ingestion), and every 30 minutes up to 120 minutes. GFV values were compared between morbidly obese and control groups and also between preingestion and postingestion time points. The morbidly obese group had a significantly higher body weight and BMI than the control group (mean body weight and BMI in morbidly obese, 129.6 kg and 46.3 kg/m, respectively; control, 59.5 kg and 21.6 kg/m, respectively). GFV was significantly higher in the morbidly obese subjects compared with the control group at preingestion (73 ± 30.8 mL vs 31 ± 19.9 mL, P = .001) and at 0 minutes after ingestion (561 ± 30.8 mL vs 486 ± 42.8 mL; P < .001). GFV declined rapidly in both groups and reached fasting baseline levels by 120 minutes (morbidly obese, 50 ± 29.5 mL; control, 30 ± 11.6 mL). A significant correlation was observed between preingestion residual GFV and body weight (r = .66; P = .001). Morbidly obese subjects have a higher residual gastric volume after 9 hours of fasting compared with subjects with a normal BMI. However, no differences were observed in gastric emptying after ORS ingestion in the 2 populations, and GFVs reached baseline within 2 hours after ORS ingestion. Further studies are required to confirm whether the preoperative fasting and fluid

  8. Detection the changes of hippocampal volume and the lateral ventricle vein in the patients with depression with susceptibility weighted imaging and morphological measurement

    International Nuclear Information System (INIS)

    Song Huihui; Li Yuefeng; Wang Dongqing; Wei Chuanshe; Duan Ruigen; Zhao Tian; Zhao Liang; Jiang Ping

    2013-01-01

    Objective: To study the hippocampal structure in the patients with depression in varying degrees of severity with the combination of the susceptibility weighted imaging (SWI) and morphological measurement. Methods: Sixty patients (divided equally into mild, moderate and major group as the conditions of the severity of depression) and 20 healthy controls were scanned using the three dimensional fast low angle shot imaging sequence (3D-FLASH) and SWI. Then the morphological images were manually segmented and delineated by three doctors. The hippocampal volumes were calculated and standardized. The maximum diameter, length and the branching numbers of the Inferior ventricular vein which were clear demonstrated in the SWI were measured. The changes in the venous system and morphology among the three different degrees of severity in depression and the healthy controls were contrastively analyzed by the one-way analysis of variance. Results: Left and right hippocampal volumes: the mild group were 2246 ± 147, 2271 ± 151; the moderate group were 2028 ± 65, 2038 ± 57; the major group were 1965 ± 129, 1962 ± 110; the healthy control were 2287 ± 160, 2305 ± 171. There were statistically significant differences among the four groups (F = 7.45, 8.55, P 0.05). The diameter,length and branch numbers of the lateral ventricle vein: the mild group were (0.94 ± 0.09) mm, (12.0 ± 1.07) mm and 3.67 ± 1.03 ; the moderate group were (0.81 ± 0.04) mm, (10.2 ± 1.25) mm and 2.00 ± 0.89 ; the major group were (0.70 ± 0.08) mm, (8.6 ± 1.40) mm and 1.83 ± 0.75 ; the healthy control were (1.15 ± 0.14) mm, (14.2 ± 0.90) mm and 3.33 ± 0.82. There were statistically significant differences among the four groups (F = 17.07, 25.20, 6.65, P 0.05). As the progressive of the depression, the reduction in the length, diameter and branch numbers of the lateral ventricle vein showed more evident (the Dunnett-t of the moderate were -10.20, -11.50, -2.88, P < 0.05 ; the Dunnett-t of the

  9. Uterine artery embolization for leiomyomas. Examination of correlation between degree of leiomyoma perfusion determined by enhanced MR i-Drive method and leiomyoma volume change on MR image

    International Nuclear Information System (INIS)

    Arimoto, Hiroshi; Yamamoto, Kazuhiro; Yamaguchi, Hiroyuki; Terai, Yoshito; Ohmichi, Masahide; Narabayashi, Isamu

    2007-01-01

    The objective of this study was to evaluate the correlations of leiomyoma volume reduction with the perfusion pattern of leiomyomas and signal intensity on T2-weighted images. Magnetic resonance (MR) imaging was performed on 11 patients with 35 symptomatic uterine leiomyomas before and 3 and 6 months after uterine artery embolization (UAE). The correlation between leiomyoma perfusion pattern and percent leiomyoma volume reduction was assessed. The mean percent leiomyoma volume reductions were 41.1% 3 months and 58.4% 6 months after UAE. The mean percent volume reductions of highly perfused leiomyomas were 58.6% 3 months and 85.7% 6 months after UAE. The reduction rates of poorly perfused leiomyomas were 37.9% 3 months and 49.1% 6 months after UAE. Well-perfused leiomyomas are more likely to reduce in leiomyoma volume. It is thought that a patient with a well-perfusion myoma is a good candidate for UAE. (author)

  10. Electroanalytical chemistry. Volume 14

    International Nuclear Information System (INIS)

    Bard, A.J.

    1986-01-01

    This volume is part of a series aimed at authoritative reviews of electroanalytical techniques and related areas of investigation. Volume 14 clearly maintains the high standards and proven usefulness of the series. Topics covered include conformation change and isomerization associated with electrode reactions, infrared vibrational spectroscopy of the electrode-solution interface, and precision in linear sweep and cyclic voltametry. A short history of electrochemical techniques which include the term square wave is provided

  11. BDNF Val66Met in preclinical Alzheimer's disease is associated with short-term changes in episodic memory and hippocampal volume but not serum mBDNF.

    Science.gov (United States)

    Lim, Yen Ying; Rainey-Smith, Stephanie; Lim, Yoon; Laws, Simon M; Gupta, Veer; Porter, Tenielle; Bourgeat, Pierrick; Ames, David; Fowler, Christopher; Salvado, Olivier; Villemagne, Victor L; Rowe, Christopher C; Masters, Colin L; Zhou, Xin Fu; Martins, Ralph N; Maruff, Paul

    2017-11-01

    The brain-derived neurotrophic factor (BDNF) Val66Met polymorphism Met allele exacerbates amyloid (Aβ) related decline in episodic memory (EM) and hippocampal volume (HV) over 36-54 months in preclinical Alzheimer's disease (AD). However, the extent to which Aβ+ and BDNF Val66Met is related to circulating markers of BDNF (e.g. serum) is unknown. We aimed to determine the effect of Aβ and the BDNF Val66Met polymorphism on levels of serum mBDNF, EM, and HV at baseline and over 18-months. Non-demented older adults (n = 446) underwent Aβ neuroimaging and BDNF Val66Met genotyping. EM and HV were assessed at baseline and 18 months later. Fasted blood samples were obtained from each participant at baseline and at 18-month follow-up. Aβ PET neuroimaging was used to classify participants as Aβ- or Aβ+. At baseline, Aβ+ adults showed worse EM impairment and lower serum mBDNF levels relative to Aβ- adults. BDNF Val66Met polymorphism did not affect serum mBDNF, EM, or HV at baseline. When considered over 18-months, compared to Aβ- Val homozygotes, Aβ+ Val homozygotes showed significant decline in EM and HV but not serum mBDNF. Similarly, compared to Aβ+ Val homozygotes, Aβ+ Met carriers showed significant decline in EM and HV over 18-months but showed no change in serum mBDNF. While allelic variation in BDNF Val66Met may influence Aβ+ related neurodegeneration and memory loss over the short term, this is not related to serum mBDNF. Longer follow-up intervals may be required to further determine any relationships between serum mBDNF, EM, and HV in preclinical AD.

  12. Effects of Dexmedetomidine Infusion on Inflammatory Responses and Injury of Lung Tidal Volume Changes during One-Lung Ventilation in Thoracoscopic Surgery: A Randomized Controlled Trial

    Directory of Open Access Journals (Sweden)

    Chun-Yu Wu

    2018-01-01

    Full Text Available One-lung ventilation in thoracic surgery provokes profound systemic inflammatory responses and injury related to lung tidal volume changes. We hypothesized that the highly selective a2-adrenergic agonist dexmedetomidine attenuates these injurious responses. Sixty patients were randomly assigned to receive dexmedetomidine or saline during thoracoscopic surgery. There is a trend of less postoperative medical complication including that no patients in the dexmedetomidine group developed postoperative medical complications, whereas four patients in the saline group did (0% versus 13.3%, p=0.1124. Plasma inflammatory and injurious biomarkers between the baseline and after resumption of two-lung ventilation were particularly notable. The plasma high-mobility group box 1 level decreased significantly from 51.7 (58.1 to 33.9 (45.0 ng.ml−1 (p<0.05 in the dexmedetomidine group, which was not observed in the saline group. Plasma monocyte chemoattractant protein 1 [151.8 (115.1 to 235.2 (186.9 pg.ml−1, p<0.05] and neutrophil elastase [350.8 (154.5 to 421.9 (106.1 ng.ml−1, p<0.05] increased significantly only in the saline group. In addition, plasma interleukin-6 was higher in the saline group than in the dexmedetomidine group at postoperative day 1 [118.8 (68.8 versus 78.5 (58.8 pg.ml−1, p=0.0271]. We conclude that dexmedetomidine attenuates one-lung ventilation-associated inflammatory and injurious responses by inhibiting alveolar neutrophil recruitment in thoracoscopic surgery.

  13. Changes in the vibrational energies and interatomic spacings upon the formation of vacancies in the volume and in the cores of crystallite conjugation regions of polycrystalline transition metals with cubic lattices

    International Nuclear Information System (INIS)

    Klotsman, S.M.; Timofeev, A.N.

    2008-01-01

    Measured changes (ε vac ) i,j of vibrational energy on vacancies formation in i-fields (in volumes and nuclei of crystallite conjugation regions of polycrystalline metals (CCR-PM)): Cr, Mo, Ta, W, Cu, Ir are presented. Changes ε vol of vibrational energy of vacancy nearest environment formed in the metal volume, changes ε FCC of vibrational energy when vacancies formation in CCR nuclei of BCC- and FCC lattices transition metals are discussed. Measured changes ε FCC of vibrational energy, u FCC potential energy and determined sign of interatomic distances changes Δa FCC when formation of split vacancy in the FCC-lattice CCR-PM, changes ε BCC of vibrational energy, u BCC potential energy and determined sign of Δa BCC changes of interatomic distances when vacancies formation in the BCC-lattice CCR-PM are demonstrated. It is noted that the increase of interatomic distances when vacancies formation in the BCC-lattice CCR nucleus of transition metals is conditioned by the the appearance of vacancies alternative structure. Properties of CCR-PM nuclei are more sensitive to interatomic distances changes in the vacancies environment, than to changes of its nearest neighbours numbers [ru

  14. Stroke volume variation compared with pulse pressure variation and cardiac index changes for prediction of fluid responsiveness in mechanically ventilated patients

    Directory of Open Access Journals (Sweden)

    Randa Aly Soliman

    2015-04-01

    Conclusions: Baseline stroke volume variation ⩾8.15% predicted fluid responsiveness in mechanically ventilated patients with acute circulatory failure. The study also confirmed the ability of pulse pressure variation to predict fluid responsiveness.

  15. Distributed Mission Operations Within-Simulator Training Effectiveness Baseline Study. Volume 5. Using the Pathfinder Methodology to Assess Pilot Knowledge Structure Changes

    National Research Council Canada - National Science Library

    Schreiber, Brian T; DiSalvo, Pam; Stock, William A; Bennett, Jr., Winston

    2006-01-01

    ...) Within Simulator Training Effectiveness Baseline Study as described in Volume I, Summary Report, of AFRL-HE-AZ-TR-2006-0015, the current work examined pilots who participated in a Pathfinder data...

  16. Changes in Search Path Complexity and Length During Learning of a Virtual Water Maze: Age Differences and Differential Associations with Hippocampal Subfield Volumes.

    Science.gov (United States)

    Daugherty, Ana M; Bender, Andrew R; Yuan, Peng; Raz, Naftali

    2016-06-01

    Impairment of hippocampus-dependent cognitive processes has been proposed to underlie age-related deficits in navigation. Animal studies suggest a differential role of hippocampal subfields in various aspects of navigation, but that hypothesis has not been tested in humans. In this study, we examined the association between volume of hippocampal subfields and age differences in virtual spatial navigation. In a sample of 65 healthy adults (age 19-75 years), advanced age was associated with a slower rate of improvement operationalized as shortening of the search path over 25 learning trials on a virtual Morris water maze task. The deficits were partially explained by greater complexity of older adults' search paths. Larger subiculum and entorhinal cortex volumes were associated with a faster decrease in search path complexity, which in turn explained faster shortening of search distance. Larger Cornu Ammonis (CA)1-2 volume was associated with faster distance shortening, but not in path complexity reduction. Age differences in regional volumes collectively accounted for 23% of the age-related variance in navigation learning. Independent of subfield volumes, advanced age was associated with poorer performance across all trials, even after reaching the asymptote. Thus, subiculum and CA1-2 volumes were associated with speed of acquisition, but not magnitude of gains in virtual maze navigation. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  17. Effect of volume change of coal during plastic and resolidifying phase on the internal gas pressure in coke ovens; Sekitan nanka saikoka katei ni okeru taiseki henka ga cokes ro no nanka yoyu sonai gas atsu ni oyobosu eikyo

    Energy Technology Data Exchange (ETDEWEB)

    Nomura, S; Arima, T [Nippon Steel Corp., Tokyo (Japan)

    2000-08-01

    The coking pressure in coke oven, which is caused by the internal gas pressure in the coal plastic layer, is determined by the gas permeability of the layer. The gas permeability of the plastic layer depends on its density as well as the physical property of the plastic coal itself The plastic layer is between the coke layer and the coal layer and the effect of the volume change of these outer layers, i.e. contraction and compression, on the density and the internal gas pressure of the plastic layer was studied. Sandwich carbonization test, where different coals were charged in the test coke oven, showed that the internal gas pressure in the plastic layer depends not only on the one kind of coal in plastic phase but also on the other kind of coal in resolidifying phase near the oven walls. The relative volume of coke transformed from the unit volume of coal was measured using X-ray CT scanner and it varied greatly across the coke oven width depending on the kinds of coals. The volume change of coal during plastic and resolidifying phase affects the density and the internal gas pressure of the plastic layer The relative volume of semicoke and coke transformed from the unit volume of coal near the oven walls is higher for a high coking pressure coal than that for a low coking pressure coal. This leads to the high density of the plastic layer and the generation of dangerously high internal gas pressure in the oven centre. (author)

  18. Comparison of changes in tidal volume associated with expiratory rib cage compression and expiratory abdominal compression in patients on prolonged mechanical ventilation.

    Science.gov (United States)

    Morino, Akira; Shida, Masahiro; Tanaka, Masashi; Sato, Kimihiro; Seko, Toshiaki; Ito, Shunsuke; Ogawa, Shunichi; Takahashi, Naoaki

    2015-07-01

    [Purpose] This study was designed to compare and clarify the relationship between expiratory rib cage compression and expiratory abdominal compression in patients on prolonged mechanical ventilation, with a focus on tidal volume. [Subjects and Methods] The subjects were 18 patients on prolonged mechanical ventilation, who had undergone tracheostomy. Each patient received expiratory rib cage compression and expiratory abdominal compression; the order of implementation was randomized. Subjects were positioned in a 30° lateral recumbent position, and a 2-kgf compression was applied. For expiratory rib cage compression, the rib cage was compressed unilaterally; for expiratory abdominal compression, the area directly above the navel was compressed. Tidal volume values were the actual measured values divided by body weight. [Results] Tidal volume values were as follows: at rest, 7.2 ± 1.7 mL/kg; during expiratory rib cage compression, 8.3 ± 2.1 mL/kg; during expiratory abdominal compression, 9.1 ± 2.2 mL/kg. There was a significant difference between the tidal volume during expiratory abdominal compression and that at rest. The tidal volume in expiratory rib cage compression was strongly correlated with that in expiratory abdominal compression. [Conclusion] These results indicate that expiratory abdominal compression may be an effective alternative to the manual breathing assist procedure.

  19. Quantitative dose-volume response analysis of changes in parotid gland function after radiotherapy in the head-and-neck region

    International Nuclear Information System (INIS)

    Roesink, Judith M.; Moerland, Marinus A.; Battermann, Jan J.; Hordijk, Gerrit Jan; Terhaard, Chris H.J.

    2001-01-01

    Purpose: To study the radiation tolerance of the parotid glands as a function of dose and volume irradiated. Methods and Materials: One hundred eight patients treated with primary or postoperative radiotherapy for various malignancies in the head-and-neck region were prospectively evaluated. Stimulated parotid flow rate was measured before radiotherapy and 6 weeks, 6 months, and 1 year after radiotherapy. Parotid gland dose-volume histograms were derived from CT-based treatment planning. The normal tissue complication probability model proposed by Lyman was fit to the data. A complication was defined as stimulated parotid flow rate 50 (the dose to the whole organ leading to a complication probability of 50%) was found to be 31, 35, and 39 Gy at 6 weeks, 6 months, and 1 year postradiotherapy, respectively. The volume dependency parameter n was around 1, which means that the mean parotid dose correlates best with the observed complications. There was no steep dose-response curve (m=0.45 at 1 year postradiotherapy). Conclusions: This study on dose/volume/parotid gland function relationships revealed a linear correlation between postradiotherapy flow ratio and parotid gland dose and a strong volume dependency. No threshold dose was found. Recovery of parotid gland function was shown at 6 months and 1 year after radiotherapy. In radiation planning, attempts should be made to achieve a mean parotid gland dose at least below 39 Gy (leading to a complication probability of 50%)

  20. Induction of Inducible Nitric Oxide Synthase by Lipopolysaccharide and the Influences of Cell Volume Changes, Stress Hormones and Oxidative Stress on Nitric Oxide Efflux from the Perfused Liver of Air-Breathing Catfish, Heteropneustes fossilis.

    Directory of Open Access Journals (Sweden)

    Mahua G Choudhury

    Full Text Available The air-breathing singhi catfish (Heteropneustes fossilis is frequently being challenged by bacterial contaminants, and different environmental insults like osmotic, hyper-ammonia, dehydration and oxidative stresses in its natural habitats throughout the year. The main objectives of the present investigation were to determine (a the possible induction of inducible nitric oxide synthase (iNOS gene with enhanced production of nitric oxide (NO by intra-peritoneal injection of lipopolysaccharide (LPS (a bacterial endotoxin, and (b to determine the effects of hepatic cell volume changes due to anisotonicity or by infusion of certain metabolites, stress hormones and by induction of oxidative stress on production of NO from the iNOS-induced perfused liver of singhi catfish. Intra-peritoneal injection of LPS led to induction of iNOS gene and localized tissue specific expression of iNOS enzyme with more production and accumulation of NO in different tissues of singhi catfish. Further, changes of hydration status/cell volume, caused either by anisotonicity or by infusion of certain metabolites such as glutamine plus glycine and adenosine, affected the NO production from the perfused liver of iNOS-induced singhi catfish. In general, increase of hydration status/cell swelling due to hypotonicity caused decrease, and decrease of hydration status/cell shrinkage due to hypertonicity caused increase of NO efflux from the perfused liver, thus suggesting that changes in hydration status/cell volume of hepatic cells serve as a potent modulator for regulating the NO production. Significant increase of NO efflux from the perfused liver was also observed while infusing the liver with stress hormones like epinephrine and norepinephrine, accompanied with decrease of hydration status/cell volume of hepatic cells. Further, oxidative stress, caused due to infusion of t-butyl hydroperoxide and hydrogen peroxide separately, in the perfused liver of singhi catfish, resulted

  1. Another year, another volume

    Science.gov (United States)

    Bill Block

    2012-01-01

    This issue represents the final one in volume 76 of Journal of Wildlife Management. As this one is pretty much in the books, one cannot help but wonder what the future holds for the journal. Lenny Brennan is putting together a piece for Wildlife Society Bulletin to examine how The Wildlife Society publications have changed through time. He solicited input from past and...

  2. The magnitude and course of exercise-induced stroke volume changes determine the exercise tolerance in heart transplant recipients with heart failure and normal ejection fraction

    Czech Academy of Sciences Publication Activity Database

    Meluzín, J.; Hude, P.; Leinveber, P.; Jurák, Pavel; Soukup, L.; Viščor, Ivo; Špinarová, L.; Štěpánová, R.; Podroužková, H.; Vondra, Vlastimil; Langer, P.; Němec, P.

    2014-01-01

    Roč. 20, č. 1 (2014), s. 674-687 ISSN 1205-6626 R&D Projects: GA MŠk(CZ) LO1212 Keywords : heart failure * stroke volume index * exercise tolerance * bioimpedance Subject RIV: FA - Cardiovascular Diseases incl. Cardiotharic Surgery Impact factor: 0.758, year: 2013

  3. Prospective longitudinal MRI study of brain volumes and diffusion changes during the first year after moderate to severe traumatic brain injury

    Directory of Open Access Journals (Sweden)

    Veronika Brezova

    2014-01-01

    Higher ADC values were detected in the cortex in individuals with severe TBI, DAI and PTA > 2 weeks, from 3 months. There were no associations between ADC values and brain volumes, and ADC values did not predict outcome.

  4. Characterization of Distinct Astrocytic Populations Responding with Different Volume Changes to Oxygen-Glucose Deprivation: 3d Confocal Morphometry And Single-Cell Gene Expression Profilig

    Czech Academy of Sciences Publication Activity Database

    Benešová, Jana; Rusňáková, Vendula; Honsa, Pavel; Pivoňková, Helena;